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NERVE    WOUNDS 

SYMPTOMATOLOGY   OF  PERIPHERAL    XERVE 
LESIONS  CAUSED  BY   WAR    WOUNDS 


J.    TINEL 

ANCIEN   CHEF   DE  CLINIQUE   1.1    DE   LABORATOIRE  DL.VI  A   SALPETRIERE 


PREFACE   BY 


PROFESSOR   J.    DEJERINE 

AUTHORISED   TRANSLATION    LV 

FRED    ROTHWELL,    B.A.,    Lond. 

REVISED   AND   EDITED   BY 

CECIL  A.  JOLL,  M.B.,  M.S.,  B.Sc.Lond.,  F.R.C.S.Eng. 

SENIOR   SURGEON    RICHMOND   MILITARY    HOSPITAL 

ASSISTANT   SURGEON    ROYAL   FREE   HOSPITAL 

LATE   SURGEON-IN-CHIEF   MAJESTIC   HOSPITAL,    CROIX   KOIT.L   FRANCAISE 


NEW    YORK 
WILLIAM     WOOD    &    COMPANY 

MDCCCCXVIIl 


> 


i/- 


PRINTED  IN   GREAT   BKITA1N   BY 

WILLIAM    CLOWES   AND    SONS,    LIMITED 

LONDON   AND    BECCLES 


EDITOR'S    INTRODUCTION 

My  object  in  making  Dr.  Tinel's  book  available  in  English  has  been  to 
fill  a  very  definite  gap  in  the  literature  of  peripheral  nerve  lesions.  I  am, 
of  course,  aware  that  there  are  excellent  manuals  on  the  subject  by  British 
authors,  but  none  of  them  appears  to  me  to  cover  the  ground  so  fully,  so 
authoritatively,  and  so  originally  as  Dr.  Tinel's. 

The  continental  clinic  system  makes  it  possible  for  the  clinician  to 
investigate  a  far  larger  number  of  cases  than  under  our  own  individualistic 
methods.  I  hope  that,  with  the  return  of  peace,  the  clinic  system,  intro- 
duced in  a  modified  form  by  my  colleague,  Mr.  James  Berry,  at  the  Royal 
Free  Hospital,  will  be  continued  and  expanded. 

I  have  endeavoured  to  adhere  closely  to  Dr.  Tinel's  text.  If,  how- 
ever, I  have  failed  to  reproduce  his  meaning,  the  responsibility  is  certainly 
mine,  as  his  book  is  most  lucidlv  written. 

I  have  throughout  preserved  the  term  "  griffe "  rather  than  use  the 
rather  doubtful  translation  "  claw,"  and  in  one  or  two  other  cases  where 
translation  did  not  appear  to  be  helpful,  I  have  retained  the  original  word. 
I  wish  to  thank  Mr.  Rothwell  for  great  help  in  the  revision  of  the  proofs. 

CECIL   A.   JOLL. 

WlMPOLE    StRIET,    W. 

October,  191 7. 


<r  2 


380212 


PREFACE 

I  am  pleased  to  be  in  a  position  to  introduce  to  the  medical  public  this 
work  of  my  pupil  Tinel  on  Nerve  Wounds,  for  it  is  admirably  adapted 
to  the  needs  of  the  daily  work  of  our  military  hospitals. 

All  surgeons  and  neurologists  still  remember  how  surprised  they  were, 
during  the  early  months  of  the  War,  at  the  numerous  cases  of  peripheral 
nerve  wounds  brought  into  our  hospitals. 

It  was  a  big  subject  of  which  the  few  cases  observed  before  war  broke 
out  had  not  enabled  a  complete  study  to  be  made  ;  in  addition,  the 
uncertainty  of  our  clinical  and  diagnostic  knowledge  of  the  nature  ot 
the  lesions  was  complicated  by  the  therapeutic  aspect  of  the  problem. 

Suddenly  we  found  ourselves  confronted  with  so  many  facts  unlike 
one  another  that  it  is  easy  to  understand  our  hesitation  in  classifying  and 
interpreting  them,  and  above  all  in  pronouncing  them  amenable  or  not 
to  surgical  intervention. 

Indeed,  we  had  first  to  establish  the  exact  signification  of  the  variable 
and  differently  associated  symptoms  met  with  in  all  these  cases,  to  specify 
the  diagnostic  value  of  partial  or  total  paralysis,  of  muscular  hypotonia 
and  electrical  disturbances,  of  anaesthesia,  paresthesia,  or  pains  in  their 
various  modalities ;  to  throw  light  upon  the  problem  of  vaso-motor 
secretory  or  trophic  disturbances,  at  times  so  intense,  or  at  other  times 
scarcely  perceptible,  and  above  all  to  connect  each  of  these  symptoms 
with  the  determining  lesion.  By  close  study  of  all  these  disturbances 
and  of  their  evolution,  my  pupils  and  myself  have  been  enabled  to  set  up 
the  main  syndromes  of  nerve  interruption,  of  compression,  irritation  or 
regeneration,  and  the  syndromes  of  dissociated  or  partial  lesions. 

It  was  also  necessary  to  study  the  nerve  lesion  itself,  in  order  to 
understand  the  mechanism  of  interruption  irritation  or  compression. 
It  was  specially  important  to  become  acquainted  with  the  exact  anato- 
mical conditions  which  either  permit  of  the  regeneration  of  the  nerve 
trunks  or  make  this  impossible.  These  problems  have  been  solved  by 
histological  study  and  experimental  investigation.  We  are  now  acquainted 
with  the  particular  characters  of  neuromata  and  pseudo-neuromata  ;  we 
know  how  the  vicious  cicatrices  which  I  have  called  nerve  keloids,  and 
which  set  up  a  frequently  insurmountable  obstacle  to  the  regeneration 
of  the    axis-cylinders,  are    formed  ;    consequently,    we    are    possessed    of 


PREFACE  vii 

histological     information    which    either    calls    for    or    proscribes    surgical 
intervention. 

In  a  word,  the  same  histological  and  experimental  discoveries  have 
enabled  us  to  specify  the  normal  conditions  of  operation  ;  they  have 
demonstrated  the  illogical  nature  and  the  uselessness  of  certain  inter- 
ventions, the  utility  and  rationale  of  others  ;  they  have  not  only  encouraged 
the  practice  of  simple  liberations  and  of  nerve  sutures,  but  they  have  also 
enabled  us  to  throw  light  on  many  aspects  of  surgical  technique. 

For  long  months  all  the  laboratories,  clinics  and  neurological  centres 
of  our  country  have  given  themselves  up  to  these  investigations,  thus 
carrying  out  a  task  which  has  completed  the  unwearied  labours  of  former 
histologists,  physiologists,  and  clinicians. 

Whilst  it  must  be  confessed  that  all  our  problems  have  not  yet  been 
completely  solved,  and  there  are  still  many  obscure  points,  all  the  same 
it  may  be  affirmed  that  the  main  lines  to  be  followed  have  now  been 
traced.  The  time  has  come  to  unite  in  one  book  the  many  investigations 
which  form  the  basis  of  this  new  work. 

It  must  indeed  be  recognised  that  these  ideas  of  nerve  pathology, 
anatomy  and  physiology,  have  not  yet  gone  far  beyond  the  sphere  of  the 
neurological  and  surgical  centres.  Nerve  wounds  are  still  a  mysterious 
and  disturbing  problem  to  many  doctors.  And  yet  it  is  important  that 
these  fundamental  principles  should  be  known  to  all.  Nerve  lesions  must 
not  continue  to  remain  unknown  in  the  routine  of  hospital  life. 

No  longer  must  there  be,  for  whole  months,  useless  electrical  or 
massage  treatment  of  complete  nerve  sections,  or  the  unnecessary  excision 
of  nerves  simply  compressed,  irritated,  or  in  a  fair  way  towards  natural 
recovery.  . 

Regarding  the  prognosis  of  nerve  wounds,  or  of  the  operations  on 
them  which  are  frequently  necessary,  we  must  not  allow  opinions  to  be 
established  that  are  incorrect,  discouraging  in  their  pessimism,  or  dangerous 
in  their  optimism. 

Above  all,  we  must  not  regard  as  nerve  lesions,  functional  paralysis 
and  disability,  the  cure  of  which  is  so  easy  when  a  timely  diagnosis  has 
been  made. 

In  a  word,  it  is  not  sufficient  that  all  doctors  and  surgeons  should 
scrupulously  conform  to  the  indications  of  neurologists  ;  they  must  also 
be  co-workers.  This  is  the  best  means  of  multiplying  observations,  of 
recording  both  clinical  data  and  therapeutical  indications,  and  of  obtaining 
not  only  the  best  results  for  the  wounded,  but  also  a  solution  of  problems 
on  which  full  light  has  not  yet  been  thrown. 

It  is  for  this  reason  above  all  that  I  regard  the  publication  ot  the 
present  work  as  necessary. 

It  will  show  doctors  how  almost  all  clinical  problems  may  be  solved 
by  the  aid  of  a  few  very  simple  facts  of  general  anatomy  and   physiolog) . 


viii  PREFACE 


I  am  glad  to  see  once  more  verified  the  rule  which  I  have  always  followed, 
namely,  that  you  cannot  have  a  good  clinical   neurology  without  exact 

anatomy. 

We  shall  also  see  that  we  need  only  have  recourse  to  the  elements  of 
histology  and  nervous  physiology  in  order  to  deduce  therefrom  the  logical 
rules  of  physical  or  surgical  treatment. 

Consequently,  I  cannot  sufficiently  congratulate  the  author  of  this 
work  on  his  constant  endeavours  to  call  attention  to  the  knowledge  of 
anatomy,  physiology  or  histology,  necessary  for  an  interpretation  of  the 

facts. 

His  remarkable  qualities  of  exposition  will  also  be  noted.  One  must 
be  a  thorough  master  of  one's  subject  to  compile,  from  an  enormous 
mass  of  observations  and  documents  of  every  kind,  a  book  that  is  alike 
perfectly  clear  and  scrupulously  exact. 

The  wealth  and  choice  of  the  information  offered,  the  carefully 
executed  photographs,  the  numerous  clear  diagrams,  make  this  volume 
a  fine  study  in  symptomatology,  of  great  educational  importance,  and 
one  which  completely  fulfils  the  purpose  aimed  at  both  by  the  author 
and  by  the  publishers. 

It  is  a  pleasure  for  me  to  have  encouraged  the  idea  of  this  work  and 
witnessed  its  realisation.  Written,  so  to  speak,  in  my  very  presence,  it 
is  a  faithful  resume  of  the  investigations  entered  upon  in  my  service  by 
all  my  fellow-workers  of  the  Charcot  Clinic. 

J.  DEJERINE. 
Paris. 


CONTENTS 


Introduction 


PART    I 
GENERAL    SURVEY 

CHAPTER 

I.  Nerve  Lesions  in  War  Wounds      . 

II.  Clinical  Examination  of  a  Nerve 

III.  Electrical  Examination  ..... 

IV.  Clinical  Types 

V.  General  Diagnosis  of  Peripheral  Nerve  Lesions 


17 
37 
60 
92 


PART    II 
UPPER   LIMB 

VI.  Musculo-Spiral  Nerve 

VII.  Ulnar  Nerve 

VIII.  Median  Nerve 

IX.  Associated  Paralysis  of  the  Median  and  Ulnar  Nerves    . 

X.       MUSCULO-CUTANEOUS    NERVE 

XI.     The  Circumflex  Nerve 

XII.     Internal    Cutaneous    Nerve    and    Lesser    Internal    Cutaneou 
Nerve 

XIII.  Brachial  Plexus 

XIV.  Ischemic  Paralysis  of  the  Upper  Limb         .... 


99 
132 

170 

'9  + 
197 
201 

205 
209 
"5 


PART    III 
LOWER    LIMB 


XV.  Sciatic  Nerve     . 

XVI.  Small  Sciatic  Nerve 

XVII.  Anterior  Crural  Nerve 

XVIII.  Obturator  Nerve 


-3' 
266 

268 
-75 


CONTENTS 


CHAPTER 

XIX.  External  Cutaneous  Nerve  of  Thigh    .... 

XX.  Genito-Crural  Nerve 

XXI.  Ilio-Hvpogastric  Nerve 

XXII.  Lumbo-Sacral  Plexus 

XXIII.  Diagnosis  of  the  Lesions  of  the  Lumbo-Sacral  Plexus 


I'AGE 

277 

279 
280 
282 
29  + 


PART    IV 

CONCLUSIONS 


XXIV.     Prognosis  and  Treatment  of  Peripheral  Nerve  Lesions 

XXV.     Surgical  Treatment 

XXVI.     Electrical  Treatment 


297 
300 
308 


INDEX 


3'3 


INTRODUCTION 


The  number  of  peripheral  nerve  wounds  in  warfare  is  considerable  :  this 
has  been  one  of  the  surprises  of  the  present  war. 

Lesions  of  the  nerve  trunks  in  traumatisms  of  the  limbs  cannot  be 
estimated  at  less  than  18  to  20  per  cent,  and  this  proportion  increases 
if  we  leave  slight  wounds  out  of  account  and  consider  serious  traumatisms 
frequently  involving  one  or  more  nerves. 

This  consideration  is  most  important ;  in  every  wound  all  the  nerves 
of  the  wounded  limb  must  be  systematically  examined.  An  early  diagnosis 
of  nerve  lesions  will  alone  enable  one  fully  to  appreciate  the  gravity  and 
consequences  of  the  wound,  to  formulate  an  exact  functional  prognosis 
and  institute  proper  treatment.  Bv  surgical  intervention  at  the  right 
moment,  by  judiciously  employed  electrical  and  mechanical  treatment, 
an  early  diagnosis  of  nerve  lesions  will  enable  one  to  reduce  to  a  minimum 
one  form  of  incapacity  following  on  war  wounds.  On  the  other  hand, 
an  imperfect  knowledge  of  these  nerve  lesions  may  have  grave  results  ; 
it  may  cause  erroneous  or  unjust  calculations  as  to  the  degree  of  disability 
the  patient  will  suffer  in  the  future,  make  the  prognosis  of  the  wounds 
worse  bv  the  absence  of  the  necessary  treatment,  or  render  irreparable 
cases  of  paralysis  which  ought  to  have  been  cured. 

Any  nerve  may  be  affected  by  war  wounds ;  speaking  generally, 
statistics  show  a  certain  preponderance  in  nerves  of  the  upper  limb, 
amongst  them  the  musculo-spiral  nerve.  Our  own  statistics  enable  us  to 
form  some  idea  of  the  relative  proportion  of  the  different  nerves  affected. 

From  the  639  cases  investigated  in  this  work,  we  reach  the  following 
results  : — 

Upper  Limb. 

Musculo-spiral     .  .  .          .          .          .  •  14° 

Ulnar 84 

Median 67 

Musculocutaneous      .          .  .          .          .          .  11 

Circumflex  .......  25 

Lesions  of  the  brachial  plexus       ....  27 

Combined  serious  lesions  of  several  nerves  of  the 
upper  limb     ....... 


Total 


48 
408 


INTRODUCTION 

Lower  Limb. 

Anterior  crural    .......  II 

14 

•  •  78 

29 

37 
18 


Long  saphenous  nerve 
Sciatic  (trunk) 
Internal  popliteal  nerve 
External     do.  do. 

Posterior  tibial     . 
Musculocutaneous 
Anterior  tibial 
Short  saphenous  nerve  . 
Obturator   . 
External  cutaneous 
Ilio-inguinal  nerve 
Lumbo-sacral  plexus     . 


7 
4 

9 
1 

3 

1 

*9 


Total     231 

The  study  of  nerve  wounds  is  based  essentially  on  certain  facts  of 
general  pathological  anatomy,  and  on  a  perfect  knowledge  of  the  anatomy 
and  physiology  of  the  nerves. 

The  works  of  Waller,  of  Duchenne  of  Boulogne,  of  Philippeaux  and 
Vulpian,  of  Weir  Mitchell,  of  Letievant  ;  the  more  recent  researches  of 
Broca,  Lejars,  Claude  and  Velter,  etc,  have  already  thrown  considerable 
lio-ht  on  the  problems  involved  in  the  study  of  peripheral  nerve  lesions. 

The  innumerable  cases  observed  during  the  war,  however,  have  given 
this  study  considerable  importance  and  expansion.     . 

Since  the  outbreak  of  war,  it  has  produced  an  enormous  number  of 
works  from  the  various  neurological  centres.  It  is  impossible  to  enu- 
merate them  all  here  :  the  illuminating  writings  of  M.  and  Mme. 
Dejerine,  inspiring  the  works  of  their  pupils,  Andre-Thomas,  Jumentie, 
Mouzon,  etc.  ;  the  brilliant  investigations  of  P.  Marie  and  his  pupils, 
Mei<2;e,  Foix,  Mme.  Athanassio-Benisty,  etc.  ;  the  remarkable  studies  of 
Babinski  and  Froment  ;  of  Claude,  of  Sicard,  and  of  their  pupils  or 
assistants  ;  and  the  histological  researches  of  Nageotte,  etc. 

The  Societe  de  Neurologie  de  Paris  has  fortunately  grouped  together 
all  these  fundamental  investigations,  which  will  be  found  published  in 
the  comptes  rendus  of  this  Society,  and  analysed  in  the  valuable  numbers 
of  the  Revue  Neurologique  devoted  to  war  neurology. 

To  these  patient  and  methodical  investigations  of  neurologists  have 
been  added  the  works  of  surgeons,  recorded  and  published  for  the  most 
part  by  the  Societe  de  Chirurgie  de  Paris. 

To  this  cordial  and  unceasing  collaboration  of  neurologists  and  sur- 
geons we  are  at  present  indebted  for  the  possession  of  admirably  exact 
and  complete  information  on  nerve  wounds.  It  is  almost  a  new  science 
that  has  thus  come  into  being  since  the  war  began,  the  results  of  which 
already  surpass  our  most  enthusiastic  expectations  and  hopes. 


NERVE    WOUNDS 

PART    I 
A   GENERAL  SURVEY 

CHAPTER   I 
NERVE  LESIONS  RESULTING  FROM  WOUNDS 

The  peripheral  nerves  may  be  wounded  either  directly  or  indirectly. 

Directly,  the  wound  may  be  made  by  a  bullet  or  by  a  shell  splinter, 
when  the  nerves  are  sectioned,  torn,  perforated  or  crushed  by  the  pro- 
jectile ;  they  may  be  pierced  by  small  splinters  which  remain  within  the 
nerve  itself ;  they  may  also  be  contused  by  the  shock,  spitted  by  a  bony 


Fig.  i. — Various  types  of  ner-ve  sections. —  i.  Total  section  with  separation  of  the  seg- 
ments. 2.  Union  of  the  segments  by  fibrous  cord.  3.  Partial  section  ;  persistence 
of  a  portion  of  the  nerve.  4.  Total  section,  union  of  the  two  segments  by  cicatricial 
formation.  In  every  case  there  are  found  two  swellings  :  neuroma  on  the  central  end, 
glioma  on  the  peripheral  end. 

splinter,  compressed  by  a  fractured  bone.  They  may  be  stretched  or 
even  torn  away  by  violent  traction  :  this  frequently  happens  in  lesions 
of  the  brachial  plexus.  Finally,  they  may  be  infiltrated  by  an  interstitial 
traumatic  hemorrhage  of  the  nerve  trunk,  which  itself  is  in  a  contused 
state. 

1 


2  ....     NERVE   WOUNDS 

Indirectly,  the  peripheral  nerves  may  be  surrounded  by  callus  or  shut 
in  by  cicatricial  fibrous  tissue. 

The  macroscopic  lesions,  resulting  in  these  different  ways  may  be 
reduced  to  a  few  types. 

Complete  or  partial  sections,  with  separation  of  nerve  segments,  or 
else  with  interposition  of  cicatricial  tissue. 


Fig.  2. — Tearing*  and  crushing*. —  i.  Total  neuroma  by  crushing  of  the  nerve.— 
2.  Lateral  neuroma  by  partial  tearing.  3.  Diffuse  neuromatous  formation.  4.  Partial 
section.     5.  Partial  neuroma  after  crushing  a  portion  of  the  nerve. 

Tearings,  crushings  or  perforations,  attacking  the  whole  or  part  of  the 
nerve,  with  interstitial,  total,  central  or  lateral  neuroma. 

Compressions  or  strangulations  over  a  greater  or  less  extent ;  sometimes 
there  is  found  strangulation  by  simple  fibrous  band,  producing  above  the 


Fig.  3. — Compressions. —  1.  Compression  in  callus,  the  compression  corresponds  to  the 

narrowed  area,  forming  an  insurmountable  obstacle  above  which  the  contused  nerve 
has  produced  a  pseudo-neuroma.  2.  Very  tight  compression  ;  development  of  a 
neuroma  above  the  obstacle.  3.  Section  at  the  upper  part  of  the  pseudo-neuroma 
showing  thickening  or  the  envelopes.     4.  Simple  constriction  by  fibrous  cord. 

constriction  a  swelling  which  may  occasionally  disappear  immediately  after 
the  liberation  of  the  nerve. 

Contusions  or   attritions  of  the  nerve    are   most    frequently    shown    by 


NERVE   LESIONS    IN    NERVE   WOUNDS  3 

hemorrhagic  or  fihrous  infiltrations,  which  probably  correspond  to  two 
successive  stages  ;  in  all  likelihood  it  is  the  interstitial  hemorrhage  of 
the  nerve  for  the  most  part  which  in  the  long  run  produces  the  fibrous 
infiltration. 

Fibrous  hemorrhagic  infiltrations,  like  the  compressions  with  which 
they  are  often  allied,  would  seem  to  be  the  most  frequent  cause  of  nerve 
irritations  of  a  neuritic  type.  All  the  same,  there  exist  irritations,  some- 
times very  intense,  in  which  the  macroscopic  appearance  of  the  nerve  is 
absolutely  normal.  This  is  ordinarily  the  case  in  simple  neuralgia  and 
even  in  violent  neuralgia  of  a  causalgic  type. 

Almost  always  the  wounded  nerve  shows  not  only  lesions  of  the 
nerve  itself  but  also  important  changes  in  its  coverings  and  in  the  sur- 
rounding tissues  ;  thickening  of  the  neurilemma  which  may  even  con- 
stitute   a    voluminous    fibrous    sheath    for    the    nerve  ;  cicatricial    fibrous 


Fig.  4. — Pseudo-neuromata  resulting  from  bruising. —  i  and  z.  Recent  contusion  of  a 
nerve  with  hemorrhagic  infiltration.  3  and  +.  Long-standing  bruise,  with  fibrous 
and  neuromatous  infiltration. 

transformation  by  injury  to  the  neighbouring  connective  or  muscular  tissues, 
often  forming  an  enormous  fibrous  mass  in  which  the  nerve  is  as  it  were 
swallowed  up  and  is  frequently  very  difficult  to  recognise  and  isolate. 

Every  wounded  nerve  is  habitually  the  seat  of  a  more  or  less  bulky 
neuroma  or  pseudo-neuroma. 

We  give  the  name  neuroma  to  the  tumour  which  essentially  consists 
of  the  local  proliferation  and  entanglement  of  the  regenerated  nerve  fibres. 

The  neuroma  invariably  indicates  an  interruption  of  the  nerve  fibres 
and  an  obstacle  to  their  progress.  A  neuroma  is  found  on  the  central  end 
of  the  sectioned  nerves  or  else  above  the  fibrous  cicatrix  resulting  from  a 
tearing  or  a  perforation  and  opposing  the  regeneration  of  the  axis-cylinder 
(Dejerine's  "  nerve  keloid  "). 

On  the  other  hand,  the  tumours  formed  by  thickening  of  the  envelopes, 
by  hemorrhagic  or  fibrous  infiltration  of  the  nerve,  by  proliferation  of  the 
neuroglial  elements,  are  pseudo-neuromata. 

Pseudo-neuroma    resulting  from    bruising  takes   place   in   contusion-,   and 


4  NERVE   WOUNDS 

compressions  of  the  nerve  ;  the  tumour  which  occurs  on  the  peripheral 
end  of  a  sectioned  nerve  is  a  pseudo-neuroma  formed  by  proliferation  of 
the  neuroglial  cells  ;  it  contains  no  nerve  fibres,  but  is  really  a  glioma^  as 
Nageotte  has  shown. 

This  distinction  is  important,  for  it  results  in  very  different  therapeutic 
consequences.  The  neuroma  always  indicates  the  presence  of  an  obstacle  to 
nerve  regeneration^  it  developes  above  this  obstacle  which  must  almost  always 
be  removed. 

On  the  other  hand,  the  pseudo-neuroma  indicates  an  interstitial  lesion, 
without  proliferation  of  axis-cylinders ;  the  laminated  sheaths  which 
isolate  the  nerve  fasciculi  may  be  thickened,  but  they  are  not  destroyed  ; 
the  compressed  axis-cylinders  may  be  injured  or  interrupted,  but  there 
exists  no  essential  obstacle  to  their  regeneration  ;  the  integrity  of  the 
laminated  sheath,  on  the  contrary,  insures  conduction  of  the  regenerated 
fibres  ;  there  is  never  any  occasion  to  make  a  nerve  resection,  at  the  most, 
a  liberation  may  be  needed  ;  spontaneous  regeneration  is  almost  certain. 


HISTOLOGICAL   STUDY 

I.— PROCESSES   OF   DEGENERATION   AND   OF   REGENERATION 

A  microscopical  study  of  the  wounded  nerve  enables  us  to  analyse  the 
processes  of  degeneration  and  regeneration  of  the  nerve  trunks. 

Degeneration. — It  is  a  fundamental  and  absolute  principle  that  every 
interrupted  nerve  fibre  undergoes  centrifugal  degeneration  of  the  peripheral 
segment  below  the  interruption.  This  is  the  phenomenon  of  Wallerian 
degeneration. 

There  is  no  exception  to  this  rule  :  every  nerve  fibre  separated  from 
its  trophic  centre  (the  anterior  horn  cell  in  the  case  of  the  motor  fibres, 
the  cell  of  the  posterior  root  ganglion  in  the  case  of  the  sensory  fibres), 
inevitably  degenerates  ;  even  immediate  suture  of  the  nerve  trunk  cannot 
prevent  this  degeneration. 

Experimental  investigations  have  thrown  light  upon  the  successive 
phenomena  which  are  seen  during  this  degeneration  of  the  peripheral 
segment.  The  axis-cylinder  is  seen  to  assume  first  a  fibrillary  appearance, 
then  to  split  up  into  sinuous  fragments,  to  become  thin  and  finally 
disappear  altogether. 

At  the  same  time  we  note  the  progressive  transformation  of  the  myelin  ; 
it  loses  its  chemical  characteristics  and  comes  to  resemble  the  neutral  fats, 
it  also  becomes  stainable  by  Marchi's  method.  The  myelin  sheath  swells  in 
places  and  becomes  irregular,  sinuous  and  beaded  ;  it  splits  up  into  lumps  or 
droplets  and  at  last  completely  disappears,  absorbed  and  eliminated  by  the 
leucocytes. 

Lastly  we  witness  a  rapid  multiplication  of  the  nuclei  of  the  sheath  or 
Schwann,  the  proliferated  cells  of  which  unite  with  the  neighbouring 
connective  tissue  cells  and  with  the  leucocytes  to  absorb  the  split-up  myelin  ; 
these  are  the  granular  bodies  which  effect  a  veritable  clearing-up  of  the 
region,  and,  filled  with  the  droplets  of  degenerate  myelin,  are  eliminated  by 
way  of  the  lymphatic  and  the  blood  streams. 

The  interrupted  nerve  fibre  then  consists  only  of  a  vague  protoplasmic 
frame,  surrounded  by  the  multiplied  cells  of  the  sheath  of  Schwann.  This 
is  an  empty  sheath. 

Such,  as  a  whole  and  in  schematic  fashion,  is  the  process  of  Wallerian 
degeneration  of  the  peripheral  segment.  It  occurs  within  a  few  days,  two 
to  three  weeks  at  most,  culminating  in  the  inevitable  destruction  of  the 
nerve  fibre  below  the  interruption. 

Whilst  the  peripheral  segment  is  degenerating,  the  central  end  remains 
almost  intact.  Nevertheless  it  also  undergoes  slight  degeneration,  though 
confined   to   a  few    segments  above    the    interruption  ;    the    evolution    of 


6  NERVE   WOUNDS 

this  degeneration  is  almost  the  same  as  that  of  the  peripheral  segment. 
This  is  ascending  or  retrograde  degeneration. 

At  the  same  time,  the  original  nerve  cell  undergoes  certain  slight 
disturbances,  an  echo  of  the  peripheral  traumatism  ;  these  disturbances 
show  themselves  in  the  swelling  of  the  nucleus  and  the  chromatolysis  of 
Nissl's  granules.  For  some  days  this  cell  is  itself  incapable  of  entering 
upon  the  work  of  regeneration.  Only  after  a  few  days  does  it  resume  its 
normal  activity,  and  show  its  trophic  function  by  the  regeneration  of  the 
axis-cylinder. 

Regeneration. — The  apparent  union  of  the  sectioned  nerves  is  very 
rapid  ;  in  three  or  four  days  at  most  it  is  brought  about  between  the  seg- 
ments that  remain  in  contact,  by  the  proliferation  of  the  cells  of  the  sheath 
of  Schwann.  This  soldering,  however,  of  the  separate  segments  is  not 
regeneration,  which  is  more  tardy  ;  it  does  not  begin  until  a  few  days  have 
passed  and  is  effected  only  by  the  penetration  and  progressive  descent  of  the 
axis-cylinders  of  the  central  end  into  the  empty  sheaths  of  the  peripheral 
segment. 

As  in  the  peripheral  nerve,  so  also  among  the  scar  tissue  we  have  the 
proliferated  cells  of  the  sheaths  of  Schwann,  cells  of  the  neuroglia,  which 
seem  to  attract  and  direct  the  regenerated  axis-cylinders. 

This  directing  action  of  the  empty  sheaths  of  Schwann  on  the  axis- 
cylinders  of  the  central  end  has  been  proved  by  numerous  experiments  ; 
it  is  called  neurotropism. 

About  the  fourth  day,  we  see  the  axis-cylinder  of  the  central  end 
dividing  at  its  termination  into  very  fine  fibrils  which  slowly  progress  right 
to  the  level  of  the  section,  crossing  the  zone  of  retrograde  degeneration. 

They  proceed  across  the  "  soldering,"  attracted  and  guided  by  the 
masses  of  neuroglia  cells  :  they  scatter  about  as  though  seeking  the  cellular 
cords  representing  the  empty  sheaths  of  the  peripheral  segment  ;  they 
penetrate  into  these  sheaths  or  course  over  their  surfaces  ;  they  slowly 
advance  into  the  nerve  trunk,  which  they  gradually  reconstruct,  and  all  of 
whose  branches  they  follow  to  their  motor  or  sensory  endings. 

Whilst  these  regenerated  axis-cylinders  are  progressing,  their  myelin 
sheath  is  gradually  being  reconstructed  and  they  insensibly  resume  their 
normal  structure. 

Only  by  this  work  of  progressive  regeneration,  we  must  repeat,  is  the 
peripheral  segment  reconstructed  ;  there  is  no  other  method  of  regeneration. 

The  axis-cylinders  do  not  usually  grow  more  than  one  or  two 
millimetres  per  day  in  favourable  cases  ;  more  rapid  in  the  young  and 
slower  in  those  who  are  older.  The  consequence  is  that  the  regeneration 
of  the  nerve  always  demands  considerable  time.  It  must  also  be  added 
that  the  restoration  of  the  functions  of  the  nerve  takes  place  much  later 
than  its  anatomic  regeneration.  It  requires  the  reconstruction  of  the  nerve 
terminations  and  their  perfect  functional  adaptation. 


NERVE    LESIONS    IN    WAR   WOUNDS 

All  those  cases  in  which,  within  a  few  clays  or  even  hours,  the 
functional  restoration  of  a  sectioned  nerve  is  stated  to  have  taken  place,  are 
manifestly  errors  of  interpretation,  caused  most  frequently  by  the  motor  or 
sensory  substitution  of  neighbouring  nerves. 


Fig.  5. — Degeneration  and  regeneration  of  a  sectioned  nerve  fibre. —  1.  Fibrillation  of 
the  axis-cylinder  and  swelling  of  the  myelin.  2.  Segmentation  of  the  axis-cylinder, 
swelling  and  displacement  of  the  myelin.  Proliferation  of  Schwann's  sheath  cells. 
3.  Disappearance  of  the  axis-cylinder  ;  myelin  bulbs ;  proliferated  connective  tissue  cells 
Retrograde  degeneration.  4.  Formation  of  granular  bodies ;  elimination  of  degenerate 
myelin  by  phagocytes.  Soldering  of  fragments  by  proliferated  connective  tissue  cells. 
Retrograde  degeneration.  5.  Beginning  of  regeneration  in  the  central  end.  6.  Pro- 
gression of  the  regenerated  axis-cylinder  in  the  empty  sheath  of  the  peripheral  end. 
7.  Regeneration  of  the  peripheral  segment.     Commencement  of  myelin  reconstruction. 


II.- DEFECTIVE   REGENERATION— NEUROMATA 

In  order  that  regeneration  of  the  peripheral  segment  may  occur,  the 
two  segments  must  remain  in  contact  with  each  other,  or  at  all  events  at 
no  great  distance  apart  ;  it  has  been  shown  that  regenerated  axis-cylinders 
are  capable  of  traversing  a  certain  distance,  attracted  by  the  neurotropism 
of  the  peripheral  end. 


8  NERVE   WOUNDS 

If  the  separation  is  too  great,  or  if  the  axis-cylinders  encounter  an 
insurmountable  obstacle  between  the  two  segments,  regeneration  of  the 
peripheral  segment  is  impossible. 

The  axis-cylinders  of  the  central  end  proliferate,  but,  being  incapable 
of  reaching  the  sheaths  of  the  peripheral  segment,  they  wander  about  in 
the  cicatricial  tissue  which  impede  their  advance,  they  cluster  at  the  ex- 
tremity of  the  central  end  and  constitute  a  veritable  tumour,  the  "neuroma"  : 
or  again,  they  are  rolled  upon  one  another  in  spirals  and  return  to  their 
starting  point,  tracing  the  curious  figures  described  by  Peroncito. 

In  these  cases,  there  is  an  attempt  at  regeneration,  though  ineffec- 
tive ;  it  is  abortive  regeneration. 

This  fruitless  regeneration,  resulting  from  a  bad  coaptation  of  the 
segments,  must  not  be  mistaken  for  absence  of  regeneration.  The  latter, 
characterised  by  absence  or  delay  of  activity  in  the  processes  of  regeneration, 
results  solely  from  serious  disturbances  in  the  nutrition  of  the  nerve  cell 
or  of  the  central  segment  ;  it  is  found  only  in  aged  subjects  or  those  in 
poor  health  :  in  certain  cases  of  neuritis,  regeneration  is  also  tardy  and 
inadequate. 

Consequently  this  is  not  as  in  the  first  case  a  simple  accident,  reparable 
by  surgical  intervention,  it  is  an  essential  disturbance  and  has  serious 
consequences. 

III.— HISTOLOGICAL   LESIONS  CAUSED   BY   NERVE  WOUNDS 

We  have  summarily  described  the  general  processes  of  degeneration 
and  regeneration,  as  elucidated  by  experimental  investigations. 

The  knowledge  acquired  will  enable  us  readily  to  interpret  the  variable 
and  complex  histological  aspects,  encountered  in  traumatic  lesions  of  the 
nerves. 

1.  Section. — Section  of  the  nerve  trunks  presents  the  simplest  features 
for  histological  study. 

We  find  on  the  central  end  a  terminal  neuroma,  formed  by  the  winding 
and  rolling  of  the  proliferated  axis-cylinders  :  this  is  the  classic  amputation 
neuroma. 

More  or  less  bulky,  this  neuroma  appears  in  section  as  made  up  of 
intricate  nerve  fibres  or  even  of  regenerated  nerve  fasciculi.  Some,  in 
longitudinal  section,  appear  sinuous  and  irregular ;  the  rest,  sectioned 
transversely  or  obliquely,  fill  the  clear  spaces  which  seem  hollowed  out  in 
the  interstitial  fibrous  tissue. 

All  these  nerve  fibres  are  embedded  in  a  fibrous  tissue  which  is  more 
or  less  dense,  sprinkled  with  numerous  cells  resulting  from  the  multiplica- 
tion of  the  neuroglial  cells  of  the  sheaths  of  Schwann  ;  these  cells  seem 
specially  grouped  along  the  nerve  fasciculi  of  which  they  really  compose 
the  connective  tissue  framework. 

The  nerve  fibres  of  the  neuroma  are  already  myelinised,  but  they  are 


NERVE    LESIONS    IN    WAR    WOUNDS 


irregular  and  often  beaded  ;  we  find  in  juxtaposition  adult  fibres,  already 
bulky,  and  very  slender  and  scarcely  myelinised  young  fibres. 

Above  where  they  enter  in  the  neuroma,  the  nerve  fibres  of  the  central 
end  almost  always  show  abnormal  features  ;  some  have  undergone  fibrillary 
transformation,  others  are  irregular,  and  sometimes  present  a  barbed  aspect 


sfisff i , 

dm 


Fig.  6. — 'terminal  neuroma  of  the  central  end. — Twisting  up,  grouping  ami  inter- 
mingling of  the  fasciculi  of  regenerated  axis-cylindets.  Certain  fasciculi  are  sectioned 
longitudinally,  others  transversely.  They  are  embedded  in  rather  dense  fibrous  tissue, 
interspersed  with  the  proliferated  cells  of  the  sheath  of  Schwann,  the  cellular  columns 
of  which  accompany  the  nerve  fasciculi. 

of  which  we  shall  speak  later ;  others  have  undergone  a  kind  of  swelling  of 
their  myelin,  giving  them  a  vacuolated  appearance. 

To  sum  up,  these  features  are  but  the  remains  of  retrograde  degenera- 
tion, or  the  manifestations  of  regenerative  activity. 

The  peripheral  segment  also  presents  a  swelling,  usually  less  bulky, 
this  is  a  false  neuroma,  a  glioma,  as  Nageotte  has  shown,  composed  solely 
of  the  excessive  proliferation  of  the  cells  of  the  sheath  of  Schwann. 

These  neuroglial  cells  are  clearly  to  be  seen,  at  the  lower  part  of  the 
glioma,  set  out  in  parallel  groups  corresponding  with  the  site  of  the  nerve 
fasciculi  that  have  disappeared.      At  the  upper  part  of  the  glioma,  the  cells 


IO 


NERVE    WOUNDS 


of  the  sheaths  of  Schwann  usually  constitute  more  bulky  and  irregular 
cellular  masses,  resulting  from  unrestrained  proliferation.  Groups  and 
cellular  masses  are  plunged  in  a  fibrous  stroma,  which  is  more  or  less 
dense. 

If  the  section  is  not  too  old,  traces  of  degenerate  nerve  fibres  may  still 
be  found  in  the  form  of  "  granular  bodies"  laden  with  myelin,  or  even 
with  series  of  blocks  of  myelin  still  tracing  the  course  of  the  nerve  fibre. 


r? .!:,'.« 


MffMwtM 


15 


flWlliM. 


Fig.  7. — Glioma  of  the  peripheral  segment. — Absence  of  all  nerve  fibre.  Simple  pro- 
liferation of  the  cells  of  the  sheath  of  Schwann,  forming  cellular  columns  which 
accompany  the  empty  sheaths.  Arrangement  in  cellular  columns  is  fairly  regular  at  the 
lower  part  of  the  glioma  ;  at  its  upper  part,  in  the  neighbourhood  of  the  section,  the 
cells  form  bulky  masses  in  which  the  fascicular  arrangement  is  no  longer  recognised. 
Below,  some  granular  bodies,  laden  with  degenerate  myelin,  have  not  yet  been  com- 
pletely eliminated. 

2.  Complete  interruptions  without  break  of  continuity  of  the  nerve. — 
The  nerve  is  apparently  not  sectioned,  but  the  traumatism,  crushing  or 
rending,  has  produced  complete  interruption  of  the  nerve  fibres.  At  the 
level  of  the  wound,  there  is  observed  a  more  or  less  irregular  neuroma, 
made  up  of  cicatricial  fibrous  tissue,  the  proliferation  of  neuroglial  cells, 
and  the  grouping  of  regenerated   axis-cylinders. 

In  very  schematic  fashion,   three  different  /.ones  in  this   neuroma  may 


NERVE    LESIONS   IN    WAR   WOUNDS 


1 1 


be  described:  a  middle  zone  of  nerve |destruction  and  of  fibro-cicatricial 
scar  tissue  constituting  the  obstacle,  this  is  the  nerve  keloid  of  Dejerine  ; 
an  upper  zone  where  the  regenerated  axis-cylinders  are  piled  up  and 
grouped  above  the  obstacle  ;  and  a  lower  zone  of  neuroglial  proliferation 


Fig.  8. — Complex  neuroma. — Above,  penetration  of  the  central  end,  the  majority  ot 
whose  fibres  have  undergone  fibrillary  transformation.  Some  fibres  are  rolled  in  spiral 
form  above  the  neuioma.  In  the  middle  part,  neuroma  made  up  of  the  intercrossing 
and  grouping  of  axis- cylinder  fasciculi  (fibres  sectioned  longitudinally  or  transversely). 
In  the  lower  part  of  the  neuroma  is  found  a  denser  fibrous  tissue  which  probably 
represents  the  cicatrix  of  the  wound.  Below,  the  cells  of  the  empty  sheaths  form 
cellular  columns,  the  proliferation  of  which  forms  on  the  left  a  veritable  glioma.  On 
the  right,  a  few  regenerated  fibres  have  succeeded  in  passing  into  the  peripheral  (semi- 
diagrammatic)  segment. 

where  the  cells  of  the  sheath  of  Schwann  form,  in  the  neighbourhood 
of  the  wound,  bulky  and  disorderlv  cellular  masses,  to  resume  in  the 
lower  part  of  the  neuroma  the  more  regular  aspect  of  cellular  columns 
corresponding  to  the  degenerate  nerve  fasciculi. 

In    reality  these   three   zones  are    seldom    so    distinct  ;    they  are    partly 


12 


NERVE   WOUNDS 


confused  and  entangled,  constituting  a  complex  neuroma,  in  which  it  is 
difficult  to  distinguish  what  results  from  each  of  the  three  processes 
analysed  :  fibrous  cicatrisation,  regeneration  of  the  central  end  and 
degeneration  of  the  peripheral  segment  with  cellular  proliferation. 

The  notion,  however,  of  the  cicatricial  fibrous  obstacle  interposed 
between  the  two  segments  is  a  very  important  one.  Whether  this 
cicatricial  formation  is  clearly  limited  as  is  sometimes  seen,  constituting 
a  sort  of  fibrous  nucleus,  or  whether  it  is  diffused  and  extends  over  almost 


Fig.  9. — Pseudo-neuroma  resulting  from  bruising. — Nerve  fasciculus  contained  in  a  cica- 
tricial fibrous  mass.  The  nerve  fibres  are  not  interrupted,  but  they  are  greatly  altered. 
Most  of  them  have  undergone  fibrillary  transformation  and  have  lost  their  myelin.  Others 
have  preserved  their  normal  volume  :  some  are  swollen,  irregular,  beaded  ;  others 
have  assumed  a  special  appearance,  bristling  with  thorns  (which  probably  represent  the 
dissociation  and  impregnation  of  the  incisures  of  Lanteimann),  barbed  in  appearance. 
The  laminated  sheaths  which  separate  the  nerve  fasciculi  are  infiltrated  and  thickened, 
but  they  have  not  undergone  any  rupture  which  permits  the  egress  of  the  axis- 
cylinders  ;  by  them  the  regenerated  nerve  fibres  are  readily  conducted  towards  the 
peripheral  end. 

the  entire  neuroma,  it  always  sets  up  an  obstacle  to  the  progression  of  the 
axis-cylinders  ;  on  the  extent,  thickness  and  density  of  the  cicatricial 
fibrous  tissue  depends  the  regeneration  of  the  peripheral  segment. 

If  the  nerve  fibres  are  able  to  pass  the  obstacle  or  turn  round  it  and 
rejoin  the  empty  peripheral  sheaths,  spontaneous  regeneration  is  possible  ; 
the  neuroma  is  permeable  to  the  regenerated  axis-cylinders. 

If  the  fibrous  tissue  is  too  dense  or  of  too  great  extent,  the  neuroma 
is  impermeable,  spontaneous  regeneration  is  impossible  ;  surgical  inter- 
vention must  remove  the  obstacle  and  restore  coaptation  between  the 
two  segments  by  resection  and  suture  of  the  nerve. 

3.   Pseudo-Neuroma  resulting  from  Bruising'. — In    certain    contusions 


NERVE   LESIONS    IN    WAR    WOUNDS 


13 


or  compressions  of  the  nerve,  one  may  observe  lesions  that  arc  not  so 
deep. 

What  essentially  characterises  these  lesions  is  that  the  laminated 
sheaths  surrounding  the  nerve  fasciculi  are  not  destroyed,  they  may  be 
infiltrated  or  thickened,  but  they  have  not  undergone  any  rupture  which 
could  permit  egress  of  the  axis-cylinders  and  their  budding  outwards. 
The  frame  of  the  nerve  is,  on  the  whole,  preserved. 

The  nerve  fibres  are  seldom  interrupted,  but  only  injured  at  the  level 
of  the  lesion.  For  instance,  we  find  a  simple  swelling  or  fragmentation 
of  the  myelin,  frequently  even  demyclinisation  of  the  nerve  fibres  ;    the 


Fig.  10. — Hemorrhagic  infiltration  of  a  newe  by  recent  contusion  :  syndrome  of  severe 
nerve  irritation.  Hemorrhage  in  the  sheath  of  the  nerve  and.  interstitial  hemorrhage. 
Fibrillary  separation  of  certain  fibres,  beaded  transformation  or  barbed  appearance  ot 
the  other  fibres.     Integrity  of  the  laminated  sheaths  (Bielchowski's  method  en  masse). 

axis-cylinder  may  be  irregular,  beaded,  or  more  frequently  it  is  separated 
into  a  bundle  of  fine  fibrils  ;  very  often  we  find  a  special  appearance 
where  the  axis-cylinder  seems  bristling  with  thorns  which  probably  repre- 
sent the  displacement  and  impregnation  with  silver  of  the  incisures  of 
Lantermann  ;  a  veritable  barbed  appearance  of  the  nerve  fibres. 

There  is  always  an  interstitial  infiltration  of  the  nerve  by  a  more  or 
less  dense  connective  tissue,  with  proliferation  of  the  cells  of  the  sheath  of 
Schwann,  or  again  we  encounter  small  interstitial  hemorrhagic  effusions. 
The  envelopes  of  the  nerve  are  thickened,  sometimes  even  the  entire 
nerve  is  embedded  in  a  cicatricial  fibrous  mass  where  it  is  extremely 
difficult  to  recognise  it. 

This  causes  increased  volume  of  the  nerve,  an  elongated  or  fusiform 
pseudo-neuroma  resulting  from  the  bruising. 

In  all  cases,  however,  lesion  of  the  nerve  fibres  is  gradually  confined  to 
the  traumatised  zone  ;  the  sheaths  of  myelin  may  have  disappeared  at  this 
level,  without  the  axis-cylinders  being  interrupted  ;  consequently  there  is 
no  Wallerian  degeneration  of  the  peripheral  segment  ;  at  the  most,  certain 


14  NERVE   WOUNDS 

fibres,  more  profoundly  affected  by  the  traumatism,  end  by  degenerating. 
Most  of  the  peripheral  fibres  do  not  degenerate  ;  they  simply  indicate, 
by  certain  modifications  of  the  myelin  or  the  axis-cylinder,  the  disturb- 
ances to  their  nutrition  caused  by  the  local  injury. 

Though  the  more  severe  lesion  of  certain  nerve  fibres  may  have  deter- 
mined their  complete  interruption,  the  integrity  of  the  laminated  sheaths 
does  not  permit  egress  of  the  regenerated  fibres;  they  cannot  constitute 
a  real  neuroma ;  they  are  guided  by  the  intact  sheaths  towards  the 
peripheral  segment. 

These  lesions  resulting  from  bruising  are  not  generally  accompanied 
by  complete  paralysis  ;  when  this  latter  exists,  it  assumes  the  somewhat 
special  characteristics  of  the  paralytic  syndrome  of  compression  ;  it  is 
usually  incomplete,  temporary,  dissociated,  irregular. 

On  the  other  hand,  it  is  in  these  cases  that  we  almost  always  encounter 
the  syndrome  of  nerve  irritation  accompanied  by  trophic  pains  and  dis- 
turbances. 

The  nerve  fibres,  having  undergone  simple  partial  and  segmentary 
degeneration,  may  be  reconstituted  on  the  spot,  without  the  necessity  of 
regeneration  by  eruption  of  the  central  axis-cylinder.  They  may  thus 
very  rapidly  regain  their  functions ;  this  is  what  we  find  in  certain 
cases  of  simple  compression  after  surgical  liberation  of  the  compressed 
nerve. 

Still  it  is  not  always  so  ;  when  the  lesions,  without  being  completely 
destructive,  are  nevertheless  very  severe,  regeneration  seems  to  take  place 
exactly  as  in  cases  of  complete  interruption  ;  the  young  axis-cylinders 
proceeding  from  the  central  end  gradually  replace  the  affected,  irritated 
and  painful  fibres  of  the  peripheral  segment.  In  these  cases  of  severe 
neuritis,  regeneration  would  seem  to  be  particularly  slow  and  difficult, 
as  though  the  trophic  function  of  the  cell  itself  were  disturbed  a 
distance  by  the  painful  reactions  of  the  affected  nerve. 

IV.— DISSOCIATED  SYNDROMES  AND   PARTIAL   LESIONS 

The  various  lesions  just  investigated  may  frequently  be  found  on  the 
same  nerve  trunk,  giving  rise  in  these  cases  to  dissociated  syndromes, 
elucidated  in  the  works  of  J.  and  A.  Dejerine  and  Mouzon. 

Thus,  for  instance,  the  same  nerve  may  be  interrupted  in  one  of  its 
parts  and  simply  bruised  or  even  intact  at  other  points. 

So  also  certain  groups  of  nerve  fibres  may  have  escaped  the  more  or 
less  complete  destruction  of  the  nerve. 

Again,  a  neuroma  may  be  permeable  or  impermeable  to  regenerated 
fibres,  or  may  even  be  partially  permeable. 

*  *  *  *  * 

Whilst  we  are  at  the  present  time  well  acquainted  with  the  histological 
processes   of  nerve   interruptions   and   regenerations   as  well   as   of   nerve 


NERVE    LESIONS    IN    WAR    WOUNDS 


15 


compressions  and  irritations,  we  must  at  the  same  time  confess  our  com- 
plete ignorance  regarding  the  syndromes  produced  by  slighter  traumatisms. 

Simple  neuralgia  from  slight  contusion  of  the  nerve,  painful  syndromes 
of  causalgia  or  of  ascending  neuritis,  fleeting  paralysis  from  temporary 
compression,  are  other  obscure  problems,  of  whose  pathogen}'  we  know 
nothing. 

In  some  cases  we  meet  with  a  few  widely  disseminated  lesions  ;  in 
many  others,  on  the  contrary,  we  find  nothing  to  explain  histologically 
the  disturbances  noticed  ;  and  one  is  often  led  to  consider  the  hypothesis 
of  disturbances  arising  from  nerve  inhibition,  sympathetic  reflexes,  or 
irritation,  a  distance^  of  the  motor  or  sensory  cells  which  are  related  to 
the  fibres  involved. 

DIAGNOSIS   OF    NERVE    LESIONS 

The  different  lesions  which  a  wounded  nerve  may  present  are  shown, 
on    examination,    by    different     syndromes.     Most     frequently    they    are 


FlG.  11. —  1.  Total  interruption.  Neuroma,  above;  glioma,  below.  2.  Partial  inter- 
ruption with  lateral  pseudo-neuroma  resulting  from  bruising.  3.  Pseudo-iieuinm;i 
resulting  from  bruising  without  interruption  of  nerve  fibres.  Rarefaction  anil  fibrilla- 
tion of  axis-cylinders. 

differentiated  in  a  way  clear  enough  to  enable  one,  previous  to  any 
intervention,  to  form  a  tolerably  exact  diagnosis  of  the  anatomical  state 
of  the  nerve. 

Thus  it  is  by  a  clinical  examination  mainly  that  we  must  judge  if  an 
operation  is  necessary.      (J.  and  A.  Dejerine  and  Mouzon.) 

Before  any  intervention  takes  place,  we  must  find  out   if  the  nerve   is 


i6 


NERVE   WOUNDS 


physiologically  interrupted  or  not ;  also  if  the  interruption  is  partial  or 
total  and  which  fibres  it  affects. 

It  is  necessary  to  recognise  the  signs  of  irritation  of  the  nerve  as  a 
whole  or  of  some  of  its  fasciculi,  indicating  that  while  the  nerve  is 
preserved,  the  fibres  are  irritated. 

Above  all  we  must  find  out  if  the  neuroma  discovered  by  palpation 
is  permeable  or  not  to  the  regenerated  fibres,  i.e.  whether  or  not  signs  of 
regeneration  exist  ;  this  is  particularly  important,  as  it  indicates  clearly 
surgical  abstention  or  intervention. 

It  would  be  most  imprudent  to  trust  solely  to  objective  signs  made  in 
the  course  of  systematic   interventions  ;  for  the  macroscopic  state  of  the 


Fig.  12. —  i.  Neuroma  impermeable  to  regenerated  fibres.     2.  Neuroma  permeable  to 
regenerated  fibres.      3.  Neuroma  partially  permeable  with  intact  fasciculus. 

nerve  but  imperfectly  reveals  its  histological  state,  and  above  all  the 
physiological  state  of  the  nerve  fibres. 

Naturally  we  must  not  neglect  the  objective  examination  and  physio- 
logical exploration  of  the  nerve  exposed  by  intervention  ;  of  all  the 
processes  suggested  for  this  examination  we  shall  find  that  there  is  only 
one  that  is  logical  and  capable  of  being  utilised  :  the  electrical  exploration 
of  the  exposed  nerve  as  propounded  and  carried  out  by  P.  Marie  and 
Meige. 

It  is  the  clinical  examination,  however,  that  must  come  first  and  supply 
the  most  important  indications  ;  it  is  this  that  will  decide  if  intervention 
is  legitimate  and  will  regulate  beforehand  the  nature  of  such  intervention. 


CHAPTER   II 
CLINICAL  EXAMINATION   OF  A  NERVE 

To  be  able  to  explore  a  nerve  implies  above  all  perfect  knowledge  of  the 
anatomy  and  physiology  of  this  nerve,  its  course  and  relations,  the  number 
and  position  of  its  branches,  the  muscles  it  supplies,  and  the  cutaneous 
territory  over  which  it  is  distributed. 

The  examination  of  a  paralysed  nerve  should  not  be  made  until 
several  weeks  after  the  wound,  if  the  best  results  are  to  be  attained. 

It  must  be  made  frequently,  at  intervals  of  several  weeks,  for  the 
evolution  of  the  symptoms  is  all  important.  One  may  often  repent 
having  operated  too  soon  ;  there  is  never  any  inconvenience,  so  to  speak, 
in  postponing  surgical  intervention  to  two  and  even  three  months  after 
the  injury. 

A  nerve  requires  to  be  examined  both  minutely  and  methodically. 
The  following  system  of  examination  may  be  advised — 


I— PRELIMINARY    EXAMINATION    AND    HISTORY    OF 

THE   CASE 

1.  Examination  of  the  wound. — The  wound  must  first  be  examined, 
the  orifice  of  entrance  and  that  of  exit  located,  and,  following  the  course 
of  the  projectile,  investigation  made  as  to  what  nerve  may  have  been 
injured. 

It  is  important  to  reconstitute  the  exact  position  of  the  limb  at  the 
time  of  the  wound,  for  anatomical  relations  may  change  according  to  the 
posture. 

The  bones  situated  in  the  neighbourhood  of  the  wound  should  also  be 
explored  ;  the  existence  of  a  fracture  makes  possible  the  compression  of 
the  nerve  in  callus  or  its  damage  by  a  bony  splinter. 

Finally,  it  must  be  known  whether  or  not  there  has  been  suppuration 
in  the  wound  :  from  a  suppurating  tract  may  sometimes  flow  purulent 
matter  capable  of  producing  irritation  in  a  neighbouring  nerve. 

2.  Date  of  the  wound. — Account  must  be  taken  of  the  time  that 
has  elapsed  since  the  wound  was  received,  for  the  symptoms  may  change 
considerably  during  the  first  few  weeks. 

2 


18  NERVE   WOUNDS 

Speaking  generally,  it  is  only  two  months  after  the  wound  that  a 
clinical  examination  possesses  its  maximum  value. 

Indeed,  during  the  early  weeks,  symptoms  of  inhibition  may  be  mis- 
taken for  signs  of  destruction  ;  paralysis  or  anaesthesia  is  often  more 
extensive  or  complete  than  would  be  associated  with  the  real  lesion. 

Again,  a  certain  number  of  symptoms  appear  only  after  some  time. 
Muscular  atrophy,  hypotonia,  require  several  weeks  to  reach  their  height  ; 
the  pains  of  nerve  irritation  frequently  appear  only  after  eight  or  ten  days 
and  sometimes  increase  for  a  whole  month  ;  formication  in  a  nerve  under 
pressure  appears  only  about  the  fourth  to  the  sixth  week. 

The  electrical  reactions  of  degeneration  likewise  frequently  come 
about  only  after  three  or  four  weeks. 

Too  hasty  an  examination,  then,  would  deprive  one  of  a  certain 
number  of  important  signs  ;  whereas  it  seems  to  be  clearly  proved  that 
a  delay  of  two  or  three  months  previous  to  surgical  intervention  is 
generally  of  no  significance  as  regards  the  success  of  such  intervention. 

3.  Investigation  of  the  first  sequelae  of  the  wound. — It  is  important 
to  find  out  if  paralysis  has  been  immediate  or  has  come  about  secondarily. 
In  the  first  event,  it  is  the  nerve  itself  that  has  been  directly  injured  ;  in 
the  second,  paralysis  may  result  simply  from  compression  by  callus,  from 
being  embedded  in  a  fibrous  cicatrix,  or  even  from  the  contact  of  a  plaster 
apparatus  ;  or  again  there  may  be  the  formation,  around  the  nerve  and 
in  its  very  tissue,  of  a  hematoma  which  has  shown  itself  some  hours  after 
the  wound  and  which  would  appear  to  be  one  of  the  frequent  causes  of 
nerve  irritation. 

Afterwards  inquiry  must  be  made  into  the  phenomena  which  some- 
times indicate  immediately  the  presence  of  a  nerve  lesion. 

Certain  wounded  men  complain  of  an  immediate  and  violent  pain, 
suddenly  traversing  like  a  flash  the  entire  extent  of  the  nerve,  whether 
it  be  the  median,  the  ulnar  or  the  sciatic.  At  other  times  the  sensation 
is  one  of  painful  numbness. 

In  other  cases,  the  nerve  wound  is  accompanied  by  signs  of  motor 
irritation,  such  as  a  sudden  cramp,  a  fleeting  contraction  in  the  region 
of  the  injured  nerve,  preceding  the  appearance  of  paralysis. 

4.  Evolution  of  nerve  disturbances. —  Inquiry  will  naturally  be  made 
as  to  the  progressive  increase  or  decrease  of  motor,  sensory,  or  trophic 
disturbances. 

The  patient  will  be  questioned  as  to  the  degree  of  functional 
inconvenience  he  experiences,  as  to  his  sensations  of  pain,  of  numbness 
and  of  formication. 

Only  after  this  previous  examination  and  interrogation  can  one 
profitably  make  an  objective  examination  of  the  nerve  affected. 


CLINICAL   EXAMINATION    OF    A    NERVE  19 

II.  — CLINICAL    EXAMINATION 

I.— ATTITUDE   OF   THE   PATIENT 

All  paralysis  produces  a  characteristic  attitude  in  repose  or  during  action. 
Thus  we  have  the  droop  of  the  hand  in  musculo-spiral  paralysis,  the 
gr'iffe*  of  ulnar  paralysis,  or  steppage  in  lesions  of  the  external  popliteal 
nerve. 

These  attitudes  will  be  studied  in  the  case  of  each  nerve. 

It  is  important  not  to  confuse  paralytic  attitudes  with  those  resulting 
from  functional  inertia,  psychic  paralyses,  contractures  or  cicatricial  fibrous 
contractions. 

II.— EXAMINATION  OF  VOLUNTARY  MOVEMENT 

The  loss  of  power  of  voluntary  movement  of  a  muscle  or  a  muscular 
group  may  vary  from  simple  enfeeblement  to  complete  paralysis. 

Naturally,  it  is  discovered  by  asking  the  patient  to  execute  the  necessary 
movements,  and  opposing  to  these  movements,  if  they  exist,  a  greater  or 
less  resistance. 

In  measuring  the  scope  of  active  or  passive  movements,  one  may 
usefully  employ  either  a  "goniometer"  with  graphic  representations 
(Lortat-Jacob  and  Sezary),  or  adopt  the  process  of  moulding  the  position 
of  the  limb  with  lead  piping.  These  processes  enable  the  evolution  of 
paralysis  to  be  readily  followed. 

Still,  several  important  causes  of  error  must  be  borne  in  mind. 

(a)  Complete  paralysis  may  be  mistaken  for  a  considerable  degree  of 
weakening  of  a  muscle,  if  movement  takes  place  in  an  unfavourable 
attitude,  particularly  if  the  weakened  muscle  has  to  overcome  the  action 
of  gravity. 

For  instance,  a  greatly  weakened  biceps  or  triceps  can  effect  flexion  or 
extension  only  when,  the  elbow  being  raised  outwards  to  the  height  of  the 
shoulder,  the  fore-arm  is  able  to  move  horizontally.  The  extensors  of 
the  wrist,  too,  if  greatly  weakened,  can  raise  the  hand  only  if  the  arm 
remains  hanging  by  the  patient's  side  ;  very  feeble  contraction  is  then 
sufficient  to  impart  to  the  hand  a  slight  oscillatory  movement. 

These  processes  are  particularly  useful  when  trying  to  bring  back  the 
early  movements  which  denote  the  disappearance  of  paralysis. 

It  is  easy  to  find  for  each  muscular  group  the  attitude  in  which  the 
feeblest  movements  are  readily  discernible. 

(b)  Make  sure  that  the  patient  has  thoroughly  understood  the  order 

*  The  term  griffe  refers  to   the  claw-like   attitude  of  the   hand  in  certain  nerve  and  muscle 
lesions. — (Ed.) 


20  NERVE    WOUNDS 

given  ;  all  that  is  needed  for  this  is  to  Have  the  movement  executed  by 
the  other  limb. 

(c)  Also  ascertain  that  inability  to  execute  the  movement  is  not 
caused  by  retraction  or  contraction  of  the  antagonists,  or  by  immobilisation 
of  a  joint. 

The  passive  movements  must  consequently  be  studied. 

(d)  It  often  happens  that  the  patient  does  not  try  to  execute  the 
prescribed  movement,  either  from  a  sort  of  functional  inertia  which  rather 
frequently  follows  on  paralysis  and  artificially  prolongs  it,  or  from  a 
conviction  of  inability,  or  even  from  ill  intent. 

This  may  readily  be  discovered,  for  even  a  powerless  effort  to  execute 
the  prescribed  movement  is  always  accompanied  by  the  synergic  contraction 
of  the  neighbouring  and  antagonistic  muscles.  If  this  contraction  is 
lacking,  one  is  justified  in  suspecting  artificial  incapacity. 

(i)  In  all  suspected  cases  electrical  examination  will  enable  us  to 
judge  of  the  reality  of  paralysis,  for  if  we  are  dealing  with  functional 
inertia  or  psychic  paralysis,  the  muscle  readily  contracts  beneath  the 
faradic  current. 

All  paralysis  in  which  faradic  contractility  is  wholly  retained  must  be 
suspected,  unless  we  are  dealing  with  cerebral  lesion.  Only,  as  we  shall 
see,  in  some  rare  cases  of  slight  compression  of  the  nerve  can  faradic 
contractility  be  retained,  in  spite  of  genuine  paralysis. 

{/)  On  the  other  hand,  one  may  deny  the  existence  of  real  paralysis 
by  attributing  to  a  paralysed  muscle  the  compensatory  movements  which 
the  neighbouring  muscles  often  succeed  in  effecting. 

The  study,  then,  of  these  functional  compensations  is  very  important, 
and  should  be  made  in  the  case  of  each  nerve. 

III.— EXAMINATION   OF   THE   REFLEXES 

Examination  of  the  reflexes  affords  two  classes  of  information. 

We  may  study  in  a  reflex  the  motor  response  which  reveals  the  paralysis 
or  the  integrity  of  the  muscle  in  question.  This  applies  mainly  to  the  study 
of  the  tendon  reflexes.  Peripheral  paralysis  of  a  muscle  is  accompanied  by 
the  disappearance  of  its  reflex.  The  patellar  reflex  is  abolished  in  paralysis 
of  the  anterior  crural  ;  the  Achilles  reflex  in  paralysis  of  the  sciatic  ;  the 
olecranon  reflex  in  paralysis  of  the  triceps  ;  the  reflex  of  the  extensors  of 
the  wrist  in  musculo-spiral  paralysis,  etc. 

Whenever  a  paralysed  muscle  reacts  by  a  reflex  movement,  it  may 
be  affirmed  that  we  are  dealing  either  with  functional  or  with  central 
paralysis. 

In  peripheral  paralyses  we  often  find  inversion  of  the  reflexes,  the 
paralysed  muscle  being  incapable  of  responding  to  sensory  excitation,  a 
response  of  the  neighbouring  or  antagonistic  muscles  is  noticed.  For 
instance,  in  lesion  of  the  musculo-spiral  accompanied   by  paralysis  of  the 


CLINICAL    EXAMINATION    OF   A    NERVE  21 

triceps,  percussion  of  the  olecranon  may  cause  slight  contraction  of  the 
biceps;  this  is  the  inversion  of  the  olecranon  reflex.  This  reflex  synergic 
contraction  of  the  neighbouring  or  antagonistic  muscles  exists  normally, 
though  it  is  masked  by  the  more  vigorous  response  of  the  muscle  directly 
stimulated  ;  paralysis  of  this  muscle  makes  it  only  the  more  manifest. 

On  the  other  hand,  in  a  reflex  one  must  consider  sensory  excitation  ; 
anaesthesia  of  the  region  excited  is  shown  by  abolition  of  the  reflexes  ;  this 
applies  mainly  to  the  cutaneous  and  periosteal  reflexes. 

In  this  case  there  is  no  response,  either  from  the  muscle  appealed  to  or 
from  the  others  ;  the  reflex  is  suppressed  at  its  source,  not  only  in  its 
motor  expression. 

The  study,  however,  of  the  cutaneous  and  especially  the  periosteal 
reflexes  is  more  delicate  than  that  of  the  tendon  reflexes  and  often  supplies 
less  exact  information,  on  account  of  the  possible  diffusion  of  the  sensory 
excitation  and  of  the  frequent  superposition  of  several  nerve  regions 
especially  in  the  case  of  deep  sensibility. 

We  shall  also  study  the  different  reflexes  with  their  respective  nerve 
regions. 


IV.— OBJECTIVE   EXAMINATION   OF   THE   MUSCLES 

(a)  Muscular  atrophy. — The  muscular  atrophy  following  a  nerve 
lesion  occurs  rather  slowly  ;  it  appears  only  after  two  or  three  weeks  and 
gradually  becomes  more  pronounced  until  the  muscle  is  transformed  into 
a  thin  fibrous  cord. 

It  may  be  recognised  by  the  contour  of  the  muscular  outline ;  it  is 
mainly  judged  by  comparison  with  the  healthy  side,  and  its  progress  may 
be  followed  by  measuring  the  circumference  of  the  limb. 

Muscular  atrophy  also  varies  according  to  the  nature  of  the  lesion  ;  it 
is  more  rapid  and  pronounced  in  sections  than  in  simple  compressions,  and 
even  more  rapid  still  in  certain  nerve  irritations. 

It  retrogresses  somewhat  slowly,  and,  though  less  marked,  persists  long 
after  the  reappearance  of  the  movements. 

It  is  increased  by  immobilisation  of  the  limb,  whilst  it  may  be 
considerably  checked  by  massage  and  a  proper  electrical  treatment  of  the 
paralysed  muscle. 

Muscular  atrophy  in  nerve  lesions  is  a  somewhat  variable  symptom 
and  of  secondary  importance  in  the  diagnosis.  It  should  be  distinguished 
from  simple  atrophy  from  prolonged  inaction  of  the  muscle  and  especially 
from  reflex  atrophy,  which  is  secondary  to  the  osseous,  articular  and  tendon 
lesions. 

(/>)  Muscular  tone. — The  study  of  muscular  tone  is  very  important,  as 
J.  and  A.  Dejerine  and  Mouzon  have  shown. 


22 


NERVE   WOUNDS 


Tone  is  the  state  of  latent  and  permanent  contraction  of  the  normal 
muscle  at  rest. 

All  paralyses  by  nerve  lesions  are  accompanied  by  muscular  hypotonia, 

but  simple  compressions  are  usually 
characterised  by  the  retention  of  a 
certain  degree  of  muscular  tone, 
whereas  complete  interruption  of 
the  nerve  after  some  time  causes  its 
total  disappearance. 

Nerve  irritations,  on  the  other 
hand,  are  not  accompanied  by  very 
marked  hypotonia  ;  it  is  frequently 
less  marked  than  in  simple  com- 
pressions. 

On  palpation,  muscular  tone 
may  be  recognised  by  the  greater 
or  less  flaccidity  of  the  muscular 
bellies. 

It  may  more  readily  be  studied  by 
causing  the  antagonistic  muscles  to  contract ;  then,  if  tone  is  maintained, 
a  slight  synergic  swelling  of  the  paralysed  muscles  is  perceived. 

The  degree  of  tone   is  even  better  recognised  by  the  attitude  of  the 
limb,  for  the  disappearance   of   tone   somewhat    intensifies  the   paralytic 


Fig.  13. — Complete  hypotonia  in  inter- 
ruption of  the  musculo-spiral  nerve. 


FlG.  14.— Return  of  muscular  tone  73  days  after  suture,  in  the  preceding  case. 

attitude.  For  instance,  in  musculo-spiral  paralysis  from  simple  com- 
pression, the  hand  remains  hanging  down  at  the  end  of  the  fore-arm, 
but  if  slight  pressure  is  given  to  the  hand,  tending  further  to  accentuate 
the  flexion  of  the  wrist  — this  accentuation  is  found  to  be  possible  since  the 
hand  was  not  flexed  to  its  full  extent — and  if  the  pressure  exercised  is 
suddenly    released,    the    hand    rises   slightly,    elastically,   owing    to   some 


CLINICAL   EXAMINATION    OF    A    NERVE  23 

remaining  muscular  tone.  In  complete  section  of  the  musculo-spiral, 
however,  flexion  of  the  hand  after  a  few  weeks  reaches  the  maximum 
permitted  by  the  articular  ligaments. 

Disappearance  of  tone,  therefore,  is  an  important  sign  in  favour  of 
complete  interruption  of  the  nerve.     (J.  and  A.  Dejerine  and  Mouzon.) 

It  must,  however,  be  noted  that  the  prolonged  inaction  of  a  muscle, 
even  in  a  certain  number  of  functional  paralyses,  may  be  accompanied  by 
hypotonia,  which  in  time  becomes  considerable. 

(c)  Mechanical  contractility  of  the  muscle. — It  is  important  to  dis- 
tinguish muscular  tone  from  idio-muscular  contractility.  Percussion  of  a 
normal  muscle  produces  a  local  and  momentary  swelling  of  the  percussed 
muscular  fasciculi,  and  that  this  is  a  genuine  contraction  is  shown 
by  more  or  less  extended  movements.  This  is  the  idio-muscular 
reflex. 

Idio-muscular  reflexes  are  always  intensified  in  peripheral-nerve  lesions, 
even  though  there  is  considerable  hypotonia  or  even  complete  atonia. 

This  intensification  of  the  mechanical  contractility  of  the  paralysed 
muscle  is,  as  we  shall  see,  comparable  to  the  intensification  of  the  con- 
tractility of  the  muscle  under  the  galvanic  current  (galvano-tonus),  when 
excitability  of  its  nerve  at  the  motor  point  has  disappeared.  Like  con- 
traction of  the  paralysed  muscle  under  the  galvanic  current,  the  contrac- 
tion provoked  by  percussion  is  slow.  This  amplitude  and  this  slowness  of 
contraction  often  permit  a  diagnosis  of  paralysis  to  be  made.  It  con- 
stitutes a  veritable  "  mecano-diagnosis  "  (Andre-Thomas).  This  is  Sicard's 
"  mechanical  myo-diagnosis." 

In  a  word,  it  may  be  said  that,  in  a  paralysed  muscle,  contractility  from 
excitation  of  the  nerve,  whether  voluntary  or  electrical,  diminishes  or 
disappears,  whereas  the  contractility  peculiar  to  the  muscular  tissue  itself 
is  intensified  ;  the  former  is  rapid  and  short,  the  latter  is  tardy  in  appear- 
ance and  slow  in  its  execution. 

Mechanical  contractility  of  the  paralysed  muscle,  however,  diminishes 
or  even  disappears  in  time,  simultaneously  with  its  galvanic  contractility  ; 
the  atrophied  muscle,  transformed  into  fibrous  tissue,  has  then  lost  every 
kind  of  excitability. 

(d)  Sensibility  of  the  muscle  to  pressure. — Every  paralysed  muscle  is 
painless  under  pressure,  unless  there  exists  some  nerve  irritation.  The 
total  insensibility  to  pain  and  even  the  absolute  insensibility  of  the  muscle 
to  pressure  is  one  of  the  clear  signs  of  complete  interruption.  (J.  and 
A.  Dejerine  and  Mouzon.) 

On  the  other  hand,  pain  of  the  muscular  bellies  under  pressure  is  the 
best  sign  of  nerve  irritation  ;  it  is  even  more  pronounced  than  pain  of  the 
nerve  under  pressure. 

This  pain  may  be  extremely  acute,  rendering  impossible  all  mobilisation 
or  massage. 

It  may  exist  even  when  the  muscle  is  not  paralysed  ;  then  pressure  on 


24  NERVE   WOUNDS 

the  muscle  frequently  causes  very  painful  though  fleeting  contractions  and 
cramps.  Voluntary  contraction  also  causes  violent  pains,  to  such  an  extent 
that  false  paralyses  may  be  noticed,  resulting  from  immobilisation  of  the 
muscle  through  fear  of  pain. 

Nerve  pain  in  the  muscles  is  very  often  accompanied  by  fibrous 
contractions. 

(e)  Fibrous  contraction  of  the  muscles. — Whereas  compressions  and 
especially  nerve  sections  are  accompanied  by  hypotonia,  flaccidity  and  pro- 
gressive lengthening  of  the  muscles;  nerve  irritation,  on  the  other  hand,  is 
almost  always  accompanied  by  muscular  contraction  with  fibrous  trans- 
formation. 

A  modification  in  the  consistency  of  the  muscle  is  then  found  ;  it 
becomes  hard,  fibrous,  painful  and  adherent  to  the  neighbouring  tissues  ; 
certain  muscles  end  by  acquiring  an  almost  woody  consistence. 

At  the  same  time,  this  muscle  has  a  tendency  to  contract.  These 
muscular  contractions  progressively  limit  the  excursion  of  the  corresponding 
joint,  modify  and  so  far  restrict  the  paralytic  attitude  as  sometimes  to 
mask  it ;  finally,  they  induce  the  appearance  of  special  attitudes,  no  longer 
reducible  as  the  paralytic  attitudes  are,  but  fixed  and  frequently  difficult  to 
reduce  by  prolonged  massage  and  mobilisation.  The  fibrous  griffes  of  the 
ulnar  and  the  median,  the  contraction  of  the  posterior  muscles  of  the  leg, 
likely  to  lead  to  pes  equinus  and  to  necessitate  tenotomy,  are  so  many 
instances  of  these  nerve  contractions. 

The  muscular  examination  must  always  end  in  a  search  for  fibrous 
contraction,  by  investigating  the  passive  movements  of  the  corresponding 
joints. 

All  limitation  of  articular  movement  is  a  sign  of  neuritis ;  impossibility 
of  completely  extending  the  fingers  or  completely  flexing  them  ;  arrest  of 
dorsi-flexion  of  the  foot  at  right  or  obtuse  angles,  demonstrate  nerve  irrita- 
tion of  the  median,  ulnar,  musculo-spiral  or  sciatic,  associated  or  not  with 
paralysis  of  these  nerves. 

One  must  naturally  avoid  confusing  nerve  muscular  contraction  with 
articular  lesions  and  especially  with  the  cicatricial  contractions  and 
adhesions  of  muscles  or  tendons,  approximately  ending  in  almost  the 
same  attitudes  and  the  same  limitation. 

(/)  Muscular  contraction  and  hypertonia. — Lastly,  certain  cases  of 
nerve  irritation,  mostly  slight,  are  accompanied  by  a  state  of  muscular 
hypertonia,  sometimes  going  as  far  as  real  contraction  ;  thus  we  meet 
with  attitudes  that  are  permanent  and  paradoxical,  in  some  way  the 
opposite  of  paralytic  attitudes,  reducible  with  difficulty  and  even  at  times 
almost  impossible  to  overcome.  The  pain  in  the  muscles  under  pressure, 
intensification  of  the  idio-muscular  reflexes,  the  sensory,  vaso-motor  or 
secretory  disturbances  met  with  in  these  cases,  particularly  the  increase 
of  the  secretion  of  sweat  (Babinski)  show  clearly  the  irritated  condition  of 
the  nerve  fibres. 


CLINICAL   EXAMINATION    OF   A   NERVE  25 

Almost  always,  however,  in  these  contractions,  especially  when  per- 
manent, we  meet  with  an  important  functional  factor  ;  they  are  certainly 
emphasised  and  intensified  by  inaction  of  the  patient. 


V.— OBJECTIVE  EXAMINATION  OF  THE  INTEGUMENTS 
AND  SUPPORTING  TISSUES.  TROPHIC  AND  VASO- 
MOTOR  DISTURBANCES 

After  the  objective  examination  of  the  muscles  comes  logically  that 
of  the  other  tissues,  investigation  of  the  various  trophic  and  vaso-motor 
disturbances. 

Speaking  generally,  we  may  lay  down  the  principle  that  trophic  dis- 


Fig.  15. — Cutaneous  disturbances  in  a  case  of  nerve  irritation.     (Note  the  smoothness 
of  the  fingers  of  the  left  hand  and  the  disappearance  of  the  cutaneous  folds.) 

turbances  are  either  absent  or  very  slight  in  almost  all  cases  of  nerve 
interruption  or  simple  compression. 

On  the  other  hand,  they  are  almost  constant  in  nerve  irritations. 

(a)  Integuments. — Examination  of  the  integuments  is  bv  far  the  most 
important  and  may  reveal  very  different  disturbances. 

Glossy  skin  is  the  most  frequent ;  disappearance  or  diminution  of  the 
cutaneous  folds,  levelling  of  the  papillary  crests  expressed  by  the  smooth 
appearance  of  the  finger-prints — constitute  its  main  characteristics. 


26 


NERVE   WOUNDS 


These  disturbances  always  exist,  though  greatly  diminished,  in  paralysis 
from  section  or  simple  compression. 

On  the  other  hand,  they  are  most  marked  in  cases  of  nerve  irritation. 
In  these  cases  we  are  struck  by  the  glossy  condition  of  the'skin,  its  dryness 
and  dull  colour,  the  disappearance  of  the  cutaneous  folds,  the  fibrous  con- 
sistence of  the  integuments  which  are  adherent  to  the  underlying  tissue 
and  difficult  to  mobilise:  these  disturbances,  always  more  pronounced  at 
the  extremities,  give  the  hand  and  foot  a  waxy  and  fixed  aspect  which  is 
altogether  characteristic. 

(b)  Sweat  reactions. — The  skin  of  paralysed  hands  and  feet  is  often 
the  seat  of  excessive  sweating,  of  fetid  odour.     This  sweating  is  mainly 


Fig.  i 6. — Cutaneous  desquamation  in  the  region  or"  the  ulnar  (slight  nerve 

irritation). 


found  in  nerve  irritations  with  slight  neuritis  and,  above  all,  in  neuralgia, 
occurring  without  complete  paralysis. 

Dryness  of  the  skin  is  very  important ;  it  is  found  in  most  cases  or 
nerve  section  and  is  sometimes  accompanied  by  a  fine  branny  desquama- 
tion which  clearly  delineates  the  cutaneous  topography  of  the  nerve.  But 
it  is  also  very  pronounced  in  certain  cases  of  nerve  irritation,  especially  in 
severe  cases  with  paralysis,  where  there  is  also  found  an  abundant  cutaneous 
desquamation  in  broad  scales.  The  skin,  thickened  and  indurated,  assumes 
quite  a  rough,  scaly,  fish-skin  appearance. 

We  may  advantageously  test  for  sweat  secretions  'with  the  aid  of 
chemical  paper  impregnated  for  instance  with  nitrate  of  silver,  or  more 
simply  by  using  litmus  paper  ;  the  slight  acidity  of  sweat  changes  blue 
litmus  paper  to  red.      (Claude  and  Chauvct,  Jumentic.) 


CLINICAL    EXAMINATION    OF    A    NERVE  27 

(f)  Vaso-motor  disturbances. — Vasomotor  disturbances  arc  practically 
inevitable  in  all  nerve  lesions. 

In  some  cases  we  find  pallor  of  the  integuments,  along  with  the 
dryness  and  thickening  of  the  skin.  It  is  mainly  found  on  the  palms  of 
the  hands  and  the  soles  of  the  feet,  where  the  thickness  of  the  integu- 
ments and  their  dull  tint  seem  to  mask  the  colouring  of  the  deeper 
planes. 

Cyanosis  and  redness  of  the  integuments  are  far  more  frequent. 

Cyanosis  more  especially  indicates  vaso-motor  paralysis,  acting  upon 
the  vaso-constrictor  apparatus.  It  is  exaggerated  by  a  dependent  position 
and  by  cooling  ;  it  rapidly  diminishes  and  disappears  if  the  limb  is  placed 
in  an  elevated  position. 

We  need  only  compare  the  cyanosis  and  the  pallor  produced  in  the 
healthy  limb  and  in  the  paralysed  one,  when  placed  alternately  in 
dependent  and  elevated  positions,  to  see  that  the  paralysed  limb  becomes 
cyanosed  more  quickly  and  pales  more  rapidly  than  the  healthy  limb. 
The  white  spot,  likewise  produced  by  pressure  of  the  finger,  disappears 
more  quickly  on  the  paralysed  limb. 

In  a  word,  these  phenomena  show  the  loss  of  tone  of  the  vaso-con- 
strictor muscles  in  the  paralysed  region. 

In  certain  conditions,  however,  one  may  notice  an  apparently  para- 
doxical phenomenon.  If  the  cyanosed  limb  is  not  in  too  dependent  a 
position,  and  the  venous  pressure  not  too  great,  vigorous  rubbing  with  the 
nail  often  produces  a  white  streak  which  slowly  enlarges  and  may  persist 
for  one  or  two  minutes.  On  the  sound  limb,  however,  the  narrow  white 
streak  obtained  by  the  nail  rapidly  disappears  and  gives  way  to  the  usual 
red  streak.  Probably  this  paralytic  white  streak  results  from  the  slow  and 
prolonged  contraction  of  the  vaso-constrictor  muscles,  brought  out  by 
mechanical  excitation.  Like  the  other  muscles,  the  paralysed  muscular 
fibres  of  the  small  vessels  seem  to  have  lost  their  nervous  excitability, 
whilst  their  idio-muscular  contractility  has  become  intensified. 

On  the  other  hand,  redness  of  the  skin  is  found  especially  in  neuritic  or 
slight  neuralgic  irritations,  without  paralysis.  It  is  particularly  marked  in 
causalgia,  and  usually  coincides  with  increase  of  the  sweat  secretions. 
Probably  it  corresponds  to  active  vaso-dilatation. 

Redness  or  cyanosis  of  the  skin  may  in  certain  cases  reach  an  extreme 
degree  ;  for  instance,  we  find  the  index  finger  in  certain  irritations  of  the 
median,  and  the  little  finger  in  certain  lesions  of  the  ulnar,  assume  a  red, 
wine-coloured,  cedematous  and  shiny  aspect  ;  the  fingers  are  covered  with 
chilblains.  The  special  susceptibility  of  the  paralysed  extremities  to 
chilblains  must  also  be  remarked. 

GEdema  is  sometimes  found  in  nerve  interruptions  ;  for  the  most  part  it 
would  seem  to  be  only  the  intensified  swelling  by  stasis  observed  in 
prolonged  dependent   positions  ;  this  is  an  oedema  of  posture  and   disuse. 


28 


NERVE   WOUNDS 


Along  with  cyanosis  it  sometimes  produces  appearances  recalling  that  of  the 
"  succulent  hand  "  in  syringomyelia. 

Then  again,  oedema  is  evidently  the  result  of  nerve  irritation  j  it  may 
reach  a  considerable  degree ;  in  these  cases  we  have  seen  it  rapidly 
disappear  as  the  result  of  surgical  intervention. 

Finally,  it  will  not  be  forgotten  that  oedema,  like  cyanosis,  often 
results  from  vascular  lesions  associated  with  nerve  lesions  ;  these  must  be 
systematically  investigated. 


In  all  these  cases,  the  distribution  of  the  vaso-motor  disturbances  is 
exactly  spread  over  the  cutaneous  region  of  the  affected  nerves.      Claude 

and  Chauvet  justly  remark  that  this  vascular 
topography  is  often  more  precise  and  exact, 
more  in  conformity  with  the  anatomical  region 
of  the  nerve,  than  the  distribution  of  the  sensory 
disturbances. 

(d)  Ulceration. — Genuine  ulceration  is  very 
rare  in  peripheral  nerve  lesions.  Almost  always 
we  can  find  the  exciting  cause. 

For  instance,  these  are  secondarily  ulcerated 
bullous   lesions,  that  have    appeared   after   too 
hot  a  bath  or  after  a  too  intense  galvanic  bath  ; 
they    have    the    characteristics    of  burns,  and 
indeed  they  doubtless  are  burns  appearing  over 
a  region  of  disturbed  nutrition,  or  else  ulcera- 
tion caused    by  the  pressure  of  an  apparatus, 
or  again   we  are   dealing    with    a    perforating 
ulcer  on  the  sole  of  the  foot,  one  which  has 
developed  as  usual  at  the  site  of  a  corn  and  has 
certainly  been  caused  by  pressure  in  walking. 
In  all  cases  these  lesions,  though  rare,  are  scarcely  ever  spontaneous ; 
the  nerve  lesion  appears  only  as  a  predisposing  cause  by  reason  of  the  dis- 
turbances in  nutrition  which  it  calls  forth.     They  would   seem  to  occur 
both  in  cases  of  complete  section  and  in  nerve  irritation. 

(/)  Thermal  disturbances. — On  the  paralysed  limbs  there  may  be  re- 
marked a  lowering  or  an  elevation  of  the  local  temperature. 

Actual  persistent  rise  of  the  local  temperature  is  found  only  in  certain 
slight  nerve  irritations,  with  permanent  vaso-dilatation  and  redness  of  the 
skin. 

On  the  other  hand,  lowering  of  the  temperature  is  very  frequent. 
But  this  is  really  an  artificial  cooling,  resulting,  on  contact  with  the  air, 
from  a  less  active  circulation.  The  cooled  limb  slowly  becomes  warm  in 
bed  or  if  it  is  wrapped  in  wadding  ;  it  almost  regains  its  normal  tempera- 
ture but  again  cools  more  rapidly  than  the  sound  limb  as  soon  as  the 
surrounding  temperature  falls. 


Fig.  17. — Ulceration  in  a  case 
of  complete  interruption  of 
the  posterior  tibial  nerve. 


CLINICAL    EXAMINATION    OF    A    NERVE 


29 


Marked  and  persistent  cooling  of  a  limb  mainly  results  from  the 
vascular  lesions  associated  with  the  nerve  lesion.  It  is  then  accompanied 
by  chronic  cyanosis,  by  oedema  and  the  progressive  fibrous  infiltration 
which  characterise  ischemic  paralysis. 

(f)  Skin  appendages. — Hypertrichosis  is  almost  constant  in  all  nerve 
lesions. 

The  nails  are  specially  affected.  Whilst,  on  the  one  hand,  in  simple 
sections  or  nerve  compressions  there  is  found  only  a  simple  transverse 
groove,  changing  place  with  the  growth  of  the  nail  and  thus  marking  the 
date  of  the  paralysis  ;  on  the  other  hand,  in  nerve  irritations  there  are  found 
serious  trophic  affections  of  the  nails  ;  they  are  striated,  split,  laminated, 
thinned  at  the  edges,  curved  like  claws  or  deformed  into  the  shape  of  a 
watch  glass. 

Frequently  too  they  are  atrophied,  smaller  than  those  of  the  opposite 
side,  and  this  diminution,  associated  with  cutaneous  and  bony  atrophy, 
ends  in  a  sort  of  tapering  conical  appearance  of  the  last  phalanx  of  the 
fingers. 

(g)  Aponeuroses,  tendons,  synovial  sheaths,  bones  and  articulations. — 
The  trophic  disturbances  of  nerve  irritation  also  reach  the  deeper  planes. 

The  thickened  and  contracted  palmar  fascia  gives  the  impression  of 
cords,  to  a  certain  extent  reminding  one  of  Dupuytren's  disease  ;  the 
indurated  plantar  fascia  sometimes  presents  fibrous  nodules,  similar  to 
those  of  alcoholic  neuritis.' 


FlG.  iS. — Ankylosing  and  deforming  arthrites,  chronic  rheumatised  type,  with  atrophy 
of  the  cellular  tissue,  by  nerve  irritation,  without  vascular  phenomona,  in  a  case  ot 
stretching  of  the  two  brachial  plexuses.     (Dejerine,  Presse  Medical,;  8  July,  191 5.) 

The  thickened,  indurated,  contracted,  synovial  sheaths  are  attached  to 
the  tendons  by  adhesions  which  immobilise  them,  and,  associated  with 
neuro-muscular  contraction,  they  determine  the  formation  of  fibrous  claws. 

The  joint  may  undergo  the  same  process  of  sclerosis,  sometimes  ending 
in  actual  fibrous  ankyloses  of  the  digital  articulations. 


30 


NERVE   WOUNDS 


The  phalanges  themselves,  thickened  at  their  ends,  give  to  the  articu- 
lations of  the  fingers  a  knotty  fusiform  appearance  which  in  certain  cases 
may  recall  the  appearance  of  rheumatoid  arthritis,  or  resemble  the  "  radish 
bunch  "  of  gonorrhoea!  rheumatism. 

Osseous  decalcification  is  a  rather  common  phenomenon,  existing   in 

almost  all  nerve  lesions,  but  also 
found  in  vascular  disturbances 
and  even  after  prolonged  disuse 
of  the  limb  through  muscular  or 
tendon  lesions. 

Decalcification,  however,  is 
particularly  pronounced  in  certain 
nerve  irritations. 

Lastly,  we  may  meet  with 
actual  atrophy  of  the  paralysed 
limb  en  masse.  We  have  referred 
to  the  conical  thinning  of  the 
digital  extremities:  it  is  possible 
to  see,  especially  in  certain  cases 
of  paralysis  of  the  ulnar  or  of 
the  posterior  tibial,  atrophy  of 
hand  or  foot  en  masse  :  in  these 
cases,  with  the  muscular  atrophy 
are  associated  the  thinning  of  the 
skin,  sclerous  atrophy  of  the 
dermis  and  osseous  decalcification 
and  deformations  of  the  nails. 

In  this  analytical  description 
we  note  how  much  more  fre- 
quent and  intense  in  nerve 
irritations  than  in  simple  nerve  sections  are  all  trophic  and  vaso-motor 
disturbances.  This  is  an  important  point,  now  well  established,  and 
on  which  we  must  insist. 

There  is  only  one  condition  capable  of  producing  trophic  disturbances 
as  marked  as  neuritic  irritation  :  the  arterial  obliteration  causing  ischemic 
paralysis.  Accordingly  this  must  always  be  sought  systematically,  when 
we  find  ourselves  confronted  with  considerable  trophic  disturbances  ;  all 
the  more  so  as  it  is  frequently  associated  with  nerve  lesions,  intensifying 
and  modifying  their  clinical  features. 


Fig.  19. — Radiograph  of  hand  (palm  facing). 
Note  the  decalcification  of  the  metacarpals 
and  of  the  phalanges  of  the  thumb,  the 
middle  finger  and  especially  the  index 
finger. 


VI.— OBJECTIVE   EXAMINATION    OF   SENSIBILITY 

Here   we   are    not    dealing  with    spontaneous    pains,   noticed    by   the 
patient,  or  with  sensations  caused   by    pressure  on   the  muscles  or  nerve 


CLINICAL    EXAMINATION    OF   A    NERVE  31 

trunks.  It  is  a  general  questioning  of  the  patient,  an  objective  examina- 
tion of  muscles  or  nerve  trunks,  that  supply  us  with  this  important  know- 
ledge. 

We  are  now  simply  investigating  the  disturbances  of  objective,  super- 
ficial and  deep  sensibility. 

1.  Cutaneous  sensibilities. — Tactile,  painful  and  thermal  sensibility 
should  be  studied  in  succession. 

In  reality,  this  minute  examination  is  not  usually  necessary,  for  the 
areas  of  the  three  sensibilities  are  usually  almost  identical.  It  may  at  the 
same  time  be  stated  that  thermal  anaesthesia  is  a  little  more  widely  diffused 
than  painful  anaesthesia  and  the  latter  than  tactile  anaesthesia. 

But  here  again  we  are  liable  to  an  error  of  interpretation,  for  in  the 
case  of  each  sensibility  we  must  distinguish  the  coarse  sensation  from  the 
fine  appreciation  of  the  qualities  of  the  sensation.  This  is  the  distinction, 
set  up  by  Head,  between  protopathic  and  epicritic  sensibility  ;  the  vague 
sensation  of  touch  is  to  be  distinguished  from  the  clear  appreciation  of  the 
nature  of  the  contact  and  of  its  precise  localisation  ;  the  rudimentary 
sensation  of  pain  must  be  differentiated  from  the  ability  to  distinguish  the, 
quality  of  the  pain  ;  the  differentiation  between  hot  and  cold  must  be  dis- 
tinguished from  an  exact  appreciation  of  moderate  temperatures.  These 
are  so  many  special  sensibilities,  corresponding  to  terminal  apparatuses  all 
the  more  complex  because  they  supply  more  precise  notions  ;  in  nerve 
sections  they  disappear  with  a  rapidity  proportional  to  their  complexity 
and  become  regenerated  all  the  more  slowly  as  they  correspond  to  appa- 
ratuses more  highly  differentiated. 

Practically,  in  the  case  of  peripheral  nerves,  we  may  generally  dispense 
with  these  minute  examinations. 

Exploration  with  a  pin  alone  supplies  all  necessary  information. 
By  a  prick,  the  pin  supplies  both  tactile  and  painful  sensations  ;   by  the 
slight  pressure  it  exercises,  however  faint,  it  affords  practically  adequate 
indications  regarding  deep  sensibility. 

Speaking  generally,  it  is  possible  in  an  anaesthetic  area  to  distinguish 
three  main  zones. 

In  the  first  zone,  the  patient  feels  nothing  ;  there  is  complete  superficial 
and  deep  anaesthesia. 

In  the  second  zone,  the  patient  perceives  the  prick  of  the  pin  as  simple 
contact ;  he  replies  :  "  touch."  Probably  this  sensation  is  mainly  provoked 
by  pressure  of  the  point;  it  largely  depends  on  deep  sensibility;  in  this 
zone  there  is  superficial  anaesthesia  with  the  retention  of  deep  sensibility. 

In  the  third  zone,  in  the  neighbourhood  of  the  next  nerve  region, 
a  true  intermediate  zone,  the  patient  vaguely  feels  the  pricking ;  he 
answers:  "pricks  a  little."  There  is  simple  superficial,  tactile  and 
painful  hypo-aesthesia  ;  it  is  in  this  zone  that  slight  cutaneous  stimuli,  with 
paint  brush,  hair,  or  piece  of  cotton-wool,  begin  to  be  clearly  distinguished. 
When  we  reach  the  intact  sensory  region  of  the  neighbouring  nerve, 


32 


NERVE   WOUNDS 


the  pricking  is  keenly  felt  ;  the  more  so  as  there  sometimes  exists  slight 
marginal  hyperesthesia. 

20th  January  (139th  day  after  the  wound). 


13th  March  (51st  day  after  suture  of  the  nerve). 


Fig.  20. — Examples  of  different  disturbances  of  sensibility,  simultaneous  or  successive,  from 
ner-ve  lesion. — Extent  ot  the  zones  of  anaesthesia  and  hypo-aesthesia  to  pin-prick,  betore 
and  after  nerve  suture  in  a  case  of  complete  interruption  of  the  median.  In  the  cross 
hatched  area,  pricking  provokes  no  sensation  at  all.  In  horizontal  hatched  area,  pricking 
causes  only  a  sensation  of  contact.  In  obli(|ue  hatched  area  with  crosses  :  panestheaic 
phenomena  :  hyperesthesia  to  pain  ;  diffusion,  irradiation,  burning  sensations,  persist- 
ence of  the  sensation.  Painful  hyperesthesia  is  specially  marked  where  the  crosses  are 
replaced  by  dots. 

In  other  cases,  we  find  hyperesthesia  either  to  all  modes  of  sensibility 
or  to  pain  only,  with  hypo-aesthesia  to  the  other  sensibilities.    This  is  what 


CLINICAL   EXAMINATION   OF   A   NERVE  33 

may  be  called  painful  hypo-esthesia  :  pin-prick,  touch,  heat  and  cold  arc 
then  imperfectly  distinguished  ;  all  these  stimuli,  however,  produce  the 
same  painful,  badly  differentiated  and  localised  sensation,  diffused,  irradiated 
in  the  neighbourhood  and  persisting  for  a  few  seconds.  This  painful 
hypo-esthesia  is  the  most  frequent  form  of  paresthesia  encountered  in 
nerve  irritation. 

It  must  not  be  confused  with  paresthesia  of  nerve  regeneration.  Indeed, 
in  the  restoration  of  cutaneous  sensibilities,  we  find  at  an  early  stage 
certain  special  phenomena,  characterised  mainly  by  a  sensation  of  formication 
diffused,  imperfectly  localised,  irradiated  in  the  neighbourhood,  persistent, 
rather  disagreeable,  provoked  by  every  cutaneous  stimulation  and  particularly 
by  light  stroking. 

These  cases  of  paresthesia  last  long  and  may  persist  for  several 
months. 

2.  Deep  sensibilities. — There  must  be  studied  successively  : 

I.  Sensibility  to  pressure  ;  the  simplest  and  most  practical  instrument 
is  the  rounded  end  of  a  stylographic  pen.  Note  if  pressure  is  felt  in  the 
region  of  the  nerve.  We  have  seen  that  the  simple  pressure  of  a  pin  point 
suffices  to  rouse  deep  sensibility. 

II.  The  sense  of  attitudes,  which  consists  in  finding  out  if  the 
patient  perceives  the  movements  imparted  to  his  various  joints. 

III.  Bony  or  periosteal  sensibility,  which  is  discovered  by  means  of  a 
tuning  fork  placed  on  the  bony  projection,  and  whose  vibrations  are  more 
or  less  distinctly  perceived. 

The  study  of  deep  sensibilities  is  less  important  than  that  of  cutaneous 
sensibilities.  It  is  subject  to  more  causes  of  error,  its  results  are  less 
constant  and  the  role  of  collateral  substitutions  is  a  greater  one.  The 
region  of  deep  anesthesia  is  always  much  more  extended  than  that  of 
cutaneous  anesthesia  ;  and  we  shall  often  find,  for  instance,  that  pressure 
applied  at  the  level  of  an  anesthetic  cutaneous  region  is  fairly  well 
perceived. 

The  disappearance,  likewise,  of  deep  anesthesia  is  often  somewhat 
earlier  than  that  of  cutaneous  anesthesia  and  may  to  some  extent  permit 
of  our  anticipating  a  speedy  restoration. 

In  every  case,  after  each  examination,  the  exact  area  of  the  anesthesia 
encountered,  whether  superficial  or  deep,  must  be  drawn  up,  for  the 
permanence  and  fixity  of  the  anesthetic  region  is  one  of  the  best  signs  of 
complete  interruption.     (J.  and  A.  Dejerine  and  Mouzon.) 

On  the  other  hand,  the  region  of  anesthesia  is  found  to  vary  from  day 
to  day  in  cases  of  simple  nerve  compression. 

During  the  regeneration,  we  see  the  concentric  shrinking  of  the  zones 
of  anesthesia. 

Only    by    observation    and    comparison    of   the    successive    areas    of 

3 


34  NERVE   WOUNDS 

sensibility  shall  we  be  able  to  account  exactly  for  the  evolution  of  sensory 
disturbances  ;  this  practice  is  the  sine  qua  non  of  a  complete  examination. 

VII.— OBJECTIVE    EXAMINATION    OF   THE  NERVE 

The  objective  examination  of  the  nerve  supplies  three  important 
indications  : 

1.  Whether  the  nerve  is  painful  on  pressure  or  not. 

2.  The  existence  of  formication  provoked  by  pressure. 

3.  The  possible  discovery  of  a  neuroma. 

L  Sensibility  of  the  nerve  on  pressure. — The  nerve  does  not  feel  pain 
on  pressure  in  all  cases  of  section  or  simple  compression. 

On  the  other  hand,  it  is  very  painful  in  neuritic  or  neuralgic  irritation 
of  a  nerve  trunk;  on  pressure  is  is  painful  along  its  whole  course  below 
the  lesion. 

Sometimes  the  nerve  is  painful  even  above  the  lesion,  but  this  is  a 
somewhat  rare  complication. 

Pain  on  pressure  must  be  carefully  differentiated  from  the  sensation  of 
formication  also  provoked  by  pressure  and  having  a  totally  different 
significance. 

2.  Formication  provoked  by  pressure. — When  compression  or  percussion 
is  lightly  applied  to  the  injured  nerve  trunk,  we  often  find,  in  the  cutaneous 
region  of  the  nerve,  a  creeping  sensation  usually  compared  by  the  patient  to 
that  caused  by  electricity. 

Formication  in  the  nerve  is  a  very  important  sign,  for  it  indicates  the 
presence  of  young  axis-cylinders  in  process  of  regeneration. 

This  formication  is  quite  distinct  from  the  pain  on  pressure,  which  exists 
in  nerve  irritations. 

The  pain,  indeed,  which  essentially  indicates  irritation  of  the  axis- 
cylinders  and  not  their  regeneration,  is  almost  always  local,  perceived  at 
the  very  spot  where  the  nerve  is  compressed,  or  at  least  magnified  at  this 
spot;  it  always  co-exists  with  the  pain  in  the  muscular  bellies  under 
pressure,  very  often  the  muscles  are  more  painful  than  the  nerve. 

Formication  of  regeneration,  on  the  other  hand,  is  but  little  or  not  at 
all  perceived  at  the  spot  compressed,  but  almost  entirely  in  the  cutaneous 
region  of  the  nerve  ;  the  neighbouring  muscles  are  not  painful. 

As  a  rule,  it  appears  only  about  the  fourth  or  sixth  week  after  the 
wound.  It  enables  us  to  ascertain  the  existence  of  this  regeneration  and 
to  follow  its  progress. 

If  it  remains  fixed  and  limited  in  one  spot  for  several  consecutive  weeks 
or  months,  this  is  because  the  axis-cylinders  in  their  regeneration  have 
encountered  an  insurmountable  obstacle  and  are  forced  to  group  together 
on  the  spot  in  a  more  or  less  bulky  neuroma. 

The  fixity  of  formication  on  a  level  with  the  lesion  and  the  complete 
absence  of  formication  below  the  lesion  would  almost  warrant  our  affirming 


CLINICAL   EXAMINATION   OF   A   NERVE  35 

the  complete  interruption  of  the  nerve  and  the  impossibility  of  spontaneous 
regeneration. 

If,  on  the  other  hand,  the  regenerated  axis-cylinders  can  overcome 
the  obstacle  and  make  their  way  into  the  peripheral  segment  of  the  nerve 
we  sec  a  progressive  migration  of  the  formication  so  provoked.  Pressure 
on  the  nerve  below  the  wound  produces  this  sensation,  and  from  week  to 
week  it  may  be  met  with  at  a  spot  farther  removed  from  the  nerve  lesion. 
The  presence  of  formication  provoked  by  pressure  below  the  nerve  lesion 
warrants  our  affirming  that  there  is  more  or  less  complete  regeneration. 

The  zone  of  formication  so  brought  out  changes  its  place  on  the 
nerve  at  the  same  time  that  the  axis-cylinders  are  advancing;  it  extends 
progressively  towards  the  periphery  at  the  same  time  that  it  disappears  at 
the  level  of  the  lesion. 

The  "formication  sign"  is  thus  of  supreme  importance,  since  it 
enables  us  to  see  whether  the  nerve  is  interrupted  or  in  course  of  re- 
generation, whether  a  nerve  suture  has  succeeded  or  failed,  or  whether 
regeneration  is  rapid  and  satisfactory  or  reduced  to  a  few  insignificant 
fibres. 

Formication  lasts  a  tolerably  long  time  ;  appearing  about  the  fourth 
week,  it  persists  during  the  entire  regeneration,  />.,  for  eight,  ten,  twelve 
months  or  more,  gradually  drawing  nearer  the  extremity  of  the  limb.  It 
ceases  only  when  the  regenerated  axis-cylinders  have  almost  regained  their 
adult  stage. 

Formication,  however,  may  be  absent,  both  on  a  level  with  the  lesion  and 
below  it ;  this  absence  is  an  unfavourable  prognostic  point  ;  it  shows  that 
nerve  regeneration  is  taking  place  imperfectly,  mainly  because  of  general 
disturbances  of  nutrition. 

3.  Search  for  a  neuroma  along  the  track  of  the  nerve. — Every  nerve 
lesion  tends  to  cause  the  formation  of  a  neuroma  at  the  injured  spot.  This 
is  sometimes  a  simple  fusiform  thickening  of  the  nerve,  sometimes  a  real 
neuroma  that  is  more  or  less  bulky  ;  at  other  times,  the  nerve  is  simply 
embedded  in  a  cicatricial  fibrous  mass. 

By  careful  palpation  we  often  succeed  in  recognising  the  existence  of 
these  neuromatous  formations  ;  besides,  the  neuroma  so  compressed  is  fre- 
quently the  seat  of  pain  or  formication  which  are  provoked,  according  as 
the  axis-cylinders  which  it  contains  are  irritated  or  regenerating  re- 
spectively. 

Still,  too  much  importance  must  not  be  attached  to  the  information 
supplied  by  palpation.  First,  because  there  are  many  causes  of  error  ; 
muscular  bundles,  cicatricial  nodules  or  enlarged  glands,  may  easily  be 
taken  for  a  neuroma.  Again,  the  discovery  of  a  neuroma  affords  no 
information  whatsoever  as  to  the  physiological  state  of  the  nerve  ;  there 
are  neuromata  permeable  to  regenerated  axis-cvlinders,  and  others  which 
permit  the  passage  of  no  fibre  whatsoever.  This  is  the  main  point  of  the 
diagnosis,  with  a  view  to  the  prognosis  and  treatment. 


36  NERVE   WOUNDS 

Consequently,  search  for  the  neuroma,  involving  many  causes  of  error, 
never  indicates  anything  more  than  the  seat  of  the  lesion. 

As  we  see,  examination  of  the  nerve  logically  terminates  the  clinical 
examination  of  the  patient.  It  completes  this  examination  and  enables  us 
to  group  together  and  interpret  the  various  symptoms  obtained  by  a  study 
of  the  muscles  and  integuments. 


CHAPTER   III 
ELECTRICAL  EXAMINATION 

The  electrical  examination  is  the  indispensable  adjunct  to  the  clinical 
examination. 

To  do  this  with  precision  often  requires  the  aid  of  a  specialist.  Still, 
every  clinical  surgeon,  with  a  little  attention,  method  and  practice,  may 
make  it  in  very  simple  and  tolerably  adequate  fashion. 

The  well-established  facts  of  electro-diagnosis  have  been  for  several 
years  largely  augmented  and  illuminated  by  modern  works,  especially  by 
the  application  to  human  pathology  of  the  investigation  and  the  methods 
of  electro-physiology. 

For  greater  clearness  we  will  divide  this  study  into  two  parts. 

1.  A  setting  out  of  the  classic  methods  of  electro-diagnosis. 

2.  A  resume  of  the  recent  notions  on  electro-physiology  which  complete 
them  and  permit  of  our  interpreting  them. 

I.— CLASSIC  METHODS   OF    ELECTRO-DIAGNOSIS 

Electrical  examination  essentially  comprises  two  stages  : 
Examination  by  the  faradic  current  ; 
Examination  by  the  galvanic  current. 

1.  Examination  by  the  faradic  current  may  be  done  in  two  ways  : 

1.  By  the  unipolar  method,  involving  the  application,  on  the  nape 
of  the  neck  or  on  the  lumbar  region,  of  a  large  indifferent  electrode  and 
the  excitation  of  nerve  and  muscles  by  the  small  active  electrode  (negative 
by  preference).  It  should  be  applied  to  the  motor  point  of  the  muscle 
which  generally  corresponds  with  the  point  of  entrance  into  the  muscle  or 
the  nerve  twig  which  supplies  it. 

2.  By  the  bipolar  method,  in  which  we  apply  the  two  electrodes  to 
the  nerve  or  muscle  to  be  examined,  so  as  to  include  the  motor  point 
when  separated  by  a  few  centimetres. 

As  a  rule,  the  bipolar  method  is  but  little  used  in  faradic  examination 
of  the  muscles.  In  our  opinion,  however,  it  is  simpler  for  making  a  rapid 
examination  of  the  muscular  groups  ;  it  is  the  method  illustrated  by  the 
works  of  Duchenne  of  Boulogne. 


38  NERVE    WOUNDS 

On  the  other  hand,  examination  of  the  nerve  is  more  difficult  by  this 
method,  the  result  being  that  the  unipolar  method  is  almost  always 
preferred. 

In  any  case,  a  successive  examination  of  nerve  and  muscles  should  be 
made,  always  employing  a  vibration  of  from  one  to  three  shocks  per  second. 

Use  will  mostly  be  made  of  a  thick  wire  coil,  the  resistance  of  which 
is  no  more  than  one  to  two  ohms. 

Examination  of  the  nerve  must  be  made  carefully,  as  this  is  far  more 
painful  than  examination  of  the  muscles. 

If  possible,  it  should  be  done  above  and  below  the  nerve  lesion,  note 
being  taken  of  the  jerks  produced  in  the  corresponding  muscles. 

Indeed,  it  may  happen  that  the  excitation  of  the  nerve  above  the 
lesion  causes  no  movement  at  all,  whereas  we  note  below  the  lesion  a 
relative  retention  of  excitability.  In  this  case  there  are  two  possibilities  : 
sometimes  it  is  a  recent  lesion  where  the  peripheral  part  of  the  nerve, 
separated  from  the  central  portion,  has  not  had  time  to  degenerate  com- 
pletely ;  or  else,  in  certain  cases  of  simple  compression  of  a  nerve  trunk, 
the  lesion  is  sufficient  to  arrest  the  transmission  of  nerve  excitation,  whilst 
not  suppressing  the  trophic  action  of  the  centres  on  the  peripheral  segment 
of  the  nerve  ;  the  latter  does  not  degenerate  and  partly  retains  its  excita- 
bility :  this  is  the  phenomenon  described  by  Erb  in  musculo-spiral 
paralysis  by  compression. 

When  excitation  of  the  nerve  above  the  lesion  provokes  contractions 
in  the  muscles  supplied  by  it,  we  may  naturally  state  that  it  is  not  inter- 
rupted, at  any  rate  in  all  its  fibres. 

Faradic  exploration  of  the  muscles  with  the  thick  wire  coil  enables 
us  to  ascertain  the  entire  series  of  disturbances,  from  simple  hypo- 
excitability  to  complete  faradic  inexcitability. 

i.  Simple  hypo-excitability  is  judged  by  comparison  with  the  same 
muscle  on  the  healthy  side.  It  is  necessary  to  sheathe  the  coil  more 
deeply  to  obtain  equal  muscular  contraction.  This  will  be  more  easily 
recognised  by  seeking  on  each  side  for  the  excitation  capable  of  causing 
very  small  contractions  ;  this  is  the  faradic  threshold,  which  is  measured 
according  to  the  length  of  coil  sheathed.  It  is  unnecessary  to  remark  that 
this  method  of  measurement  is  very  uncertain,  even  altogether  incorrect, 
for  the  electric  units  produced  by  the  coil  are  not  at  all  proportional  to 
the  lengths  of  sheathing.  It  would  be  better  to  substitute  for  notation 
of  the  length  of  sheathing,  notation  in  the  quantity  of  electricitv  induced, 
a  measure  which  is  quite  a  relative  one,  and  which  some  makers  now 
inscribe  on  their  coils. 

2.  Faradic  inexcitability  always  accompanies  complete  peripheral 
paralysis.  There  is  only  one  exception  to  this  rule :  the  paradoxical 
phenomenon  just  mentioned  in  the  slight  and  fleeting  compressions  of  a 
nerve  trunk. 


ELECTRICAL    EXAMINATION  39 

Apart  from  this  particular  case,  ;i  rather  rare  one,  all  nerve  interrup- 
tion or  prolonged  compression  is  accompanied  by  faradic  inexcitability. 
This  is  one  of  the  essential  features  of  the  reaction  of  degeneration.* 

If  we  use  a  sufficiently  strong  current,  we  often  observe  the  contrac- 
tion of  the  neighbouring  and  antagonistic  muscles,  produced  by  diffusion 
of  the  current.  This  is  what  is  called  antagonistic  contraction.  It  has 
no  other  significance  than  to  demonstrate  by  comparison  the  marked 
hypo-excitability  or  the  complete  inexcitability  of  the  muscle  involved. 

Faradic  inexcitability  appears  at  an  early  stage;  it  is  one  of  the  first 
signs  of  the  RD  and  persists  for  the  entire  duration  of  the  paralysis. 
Faradic  contractility  reappears  only  very  late,  after  the  return  of  the  first 
voluntary  movements,  as  Duchenne  of  Boulogne  has  demonstrated.  But, 
we  must  also  remember,  this  law  is  only  true  if  we  use  a  wire  coil  of 
feeble  resistance. 

Examination  of  nerve  and  muscles  by  the  faradic  current  is  very 
important  for  the  clinical  surgeon,  inasmuch  as  when  complete  faradic 
inexcitability  is  established,  one  is  almost  sure  to  find  with  the 
galvanic  current  a  reaction  of  degeneration  that  is  typical  or  at  all  events 
partial. 

On  the  other  hand,  faradic  examination  enables  us  readily  to  dis- 
tinguish organic  peripheral  paralysis  from  functional  paralysis  in  which 
faradic  contractility  is  always  maintained. 

There  are  but  two  exceptions,  already  mentioned,  to  this  rule.  On 
the  one  hand,  very  recent  paralysis  in  which  the  RD  has  not  yet  come 
about ;  then  we  find  faradic  excitability  rapidly  disappearing.  On  the 
other  hand,  the  slight  nerve  compressions,  presenting  the  paradox  of  Erb, 
in  which  the  nerve  and  muscles  are  excitable  below  the  lesion,  whereas 
the  nerve  is  inexcitable  above ;  in  a  few  days  or  weeks  we  find  the 
voluntary  movements  reappearing. 

Apart  from  these  two  cases,  all  paralysis  characterised  by  maintenance 
of  a  nearly  normal  faradic  contractility  is  not  peripheral  paralysis.  It 
is  functional  paralysis,  hysterical  or  simulated  ;  or  else  of  central  origin, 
from  cerebral  lesion  or  injury  of  the  tracts  in  the  spinal  cord,  and  always 
accompanied  by  manifest  objective  symptoms,  disturbances  of  the  reflexes, 
Babinski's  sign,  etc. 

*  It  is  important  to  note  that  we  are  here  speaking  only  of  relative  faradic  inexcitability, 
which  is  determined  with  the  ordinary  instruments  and  the  thick  wire  coil.  Indeed,  we  Bball  see 
that  this  fact  is  only  true  if  we  modify  the  usual  conditions  of  examination.  Even  if  there  exists 
complete  faradic  inexcitability  with  the  thick  coil,  faradic  inexcitability  of  the  muscle  is  ap- 
parent only  ;  we  can  always  get  contraction  of  the  paralysed  muscles  either  by  utilising  far  more 
powerful  coils  or  by  greatly  increasing  the  intensity  of  the  original  current  or  even  by  causing  the 
muscles  examined  to  undergo  electrotonic  mollifications  by  the  simultaneous  passage  of  a  galvanic- 
current.  Whenever,  then,  we  speak  of  faradic  inexcitability,  we  mean  this  relative  excitability,  foi 
the  thick  wire  coil. 


40  NERVE   WOUNDS 

Faradic  examination  also  gives  us  other  information  of  less  import- 
ance:  the  faradic  sensibility  of  skin  and  muscles.  This  sensibility  seems 
to  be  the  first  to  reappear  during  nerve  regeneration. 


In  all  this  description,  we  have  considered  only  the  usual  faradic 
examination,  with  the  thick  wire  coil.  To  this  method  alone  apply  the 
classic  ideas  as  to  faradic  excitability  of  the  muscles. 

On  the  other  hand,  if  a  coil  of  greater  electro-motive  force  is  used,  a 
fine  wire  coil,  for  instance,  the  resistance  of  which  may  reach  800, 
1200  ohms  or  more,  we  find  important  modifications. 

Indeed,  in  certain  cases,  we  may  ascertain  the  persistence  of  a  slight 
faradic  contractility  in  spite  of  a  very  pronounced  partial  RD  or  even  a 
complete  RD  ;  a  rather  strong  excitation  produces  slight  muscular 
contractions,  sometimes  very  short,  oftener  slow,  like  those  produced  by 
the  galvanic  current  on  the  degenerated  muscle. 

We  may  also  see  the  return  of  faradic  excitability  as  one  of  the  first 
signs  of  nerve  regeneration,  when  the  RD  is  still  complete,  as  shown  by 
P.  Marie,  Meige  and  Mme.  Benisty.  Consequently,  investigation  of 
faradic  excitability  with  a  fine  wire  coil  might  with  propriety  supply  the 
place  of  investigation  of  galvanic  reactions  of  regeneration,  and  one  might 
follow  the  whole  progression  of  faradic  excitability  up  to  the  normal. 

Later  on  we  shall  see  how  these  apparently  paradoxical  results  may  be 
interpreted. 

In  any  case,  this  process  of  examination  is  not  to  be  recommended. 

It  requires  currents  of  relatively  great  intensity  and  consequently 
painful  ;  the  contractions  obtained  in  the  degenerated  muscles  depend 
not  only  on  the  intensity  of  the  current,  but  also  on  the  duration  of  the 
exciting  wave,  which  is  extremely  variable  ;  it  depends  on  the  charac- 
teristics of  the  coil,  on  the  phenomena  of  self-induction,  on  the  produc- 
tion of  rupture  sparks,  which  increase  the  duration  of  the  passage  of  the 
current,  etc. 

This  method,  then,  gives  inconstant  results  and  inaccurate  information, 
it  cannot  be  measured  and  so  is  greatly  inferior  to  galvanic  examination. 

On  the  other  hand,  Babinski,  Delherm,  and  Jarkovski  have  shown  that 
it  is  possible  to  cause  faradic  contraction  to  reappear  in  paralysed  muscles 
by  associating  with  faradization  the  passage  of  a  galvanic  current  into  the 
limb.  This  latent  faradic  excitability  seems  to  constitute  an  intermediate 
degree  between  hypo-excitability  and  utter  inexcitability. 

2.  Examination  by  the  galvanic  current. — This  examination  may 
also  take  place  by  the  unipolar  or  the  bipolar  method  ;  but  here  the  unipolar 
method  is  far  preferable  :  one  might  almost  say  that  it  is  practically  the  only 
one  possible. 


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44  NERVE   WOUNDS 

The  examination  is  made  with  a  large  dorsal  indifferent  electrode  and 
a  small  electrode  applied  to  the  motor  points;  this  electrode  is  made  positive 
or  negative  in  turn  by  means  of  a  current  reverser  (Courtade's  key). 

The  nerve  and  the  muscles  supplied  by  it  will  be  examined  in  turn. 

It  must  be  remembered  that  muscular  contraction  takes  place  only  at 
the  moment  of  the  closing  and  of  the  opening  of  the  current.  The  closing 
contraction,  the  stronger  one,  is  generally  the  only  one  sought  for.  The 
contraction  on  opening  the  current,  requiring  greater  intensity,  is  seen  only 
in  certain  pathological  states. 

Three  elements  of  muscular  contraction  under  the  galvanic  current 
require  special  study. 

i.  The  intensity  of  the  current  necessary  to  produce  at  the  closing  the 
minimum  contraction  ;  this  is  the  threshold  of  excitation. 

In  an  injured  nerve,  it  will  be  possible  to  ascertain  the  diminution  or 
disappearance  of  galvanic  excitability.  Galvanic  inexcitability  is  the 
absolute  rule  in  all  cases  of  interruption  of  the  nerve. 

In  the  paralysed  muscle,  on  the  other  hand,  galvanic  inexcitability  is 
a  very  rare  phenomenon  ;  •  it  is  found  only  in  cases  where  the  degenerated 
muscle  has  finally  lost  all  contractile  structure  and  has  become  transformed 
into  a  mere  bundle  of  connective  tissue.  This  is  the  last  stage,  long 
delayed,  of  muscular  degeneration. 

Almost  always  we  find  in  the  paralysed  muscle  an  apparent  simple 
hypo-excitability.  It  can  be  measured  by  the  number  of  milli-amperes 
necessary  to  obtain  contraction,  rising  from  one  or  two  (the  normal  figure) 
to  five,  ten,  or  twenty-five  milli-amperes. 

The  normal  theshold  of  galvanic  contraction  varies  according  to  the 
muscle  and  the  patient  ;  it  must  accordingly  be  sought  by  comparison 
with  the  healthy  side. 

On  the  other  hand,  it  varies  considerably  according  to  the  point  of 
excitation  of  the  muscle  ;  from  one,  two,  three  milli-amperes  by  excitation 
of  the  motor  point  the  figure  easily  rises  to  four,  five,  eight  milli-amperes 
as  soon  as  one  moves  from  this  point.  Consequently,  minute  search  must 
be  made  for  the  motor  points  of  each  muscle. 

2.  The  pole  capable  of  inducing,  with  the  same  current,  the  strongest 
contraction  ;  or  rather,  the  pole  susceptible  of  inducing  the  minimum 
contraction  with  the  weakest  current. 

We  must  therefore  compare  the  negative  threshold  and  the  positive 
threshold. 

Normally  it  is  the  negative  pole  which,  on  the  closing  of  the  current, 
induces  the  strongest  contraction  ;  this  is  expressed  in  the  following 
formula  : — 

KCC  >  ACC. 

If  contraction  is  stronger  at  the  positive  pole,  we  have  an  inversion  of 
the  polar  formula,  and  this  is  written — 

ACC  >  KCC. 


ELECTRICAL   EXAMINATION  45 

If  the  contractions  arc  equal,  there  is  said  to  be  polar  equality. 

Certain  muscles,  particularly  the  supinator  longus,  the  tibialis  amicus, 
the  peroneals,  sometimes  exhibit  normally  the  phenomenon  of  inversion  or 
of  polar  equality. 

3.  The  form  of  contraction. 

Normal  contraction  is  rapid  and  short,  a  sudden  flash. 

In  peripheral  paralysis  with  degeneration,  contraction  becomes  slow 
and  delayed. 

Frequently  when  compelled  to  use  a  current  of  considerable  intensity, 
it  is  diffused  over  the  neighbouring  or  antagonistic  muscles.  Then  there 
is  observed  an  initial  short  contraction  of  the  antagonists,  followed  by 
slow  contraction  of  the  muscles  involved.  Sometimes  it  is  difficult  to 
distinguish  this  slow  contraction  from  simple  return  of  the  stimulated 
antagonistic  muscles  to  the  normal  state. 


ELECTRICAL  SYNDROMES 

1.  Syndrome  of  nerve  interruption. — Reaction  of  complete  degene- 
ration.— In  cases  of  peripheral  paralysis  both  the  faradic  and  the  galvanic 
examination  almost  invariably  give  concordant  results,  the  sum  total  of 
which  constitutes  the  reaction  of  degeneration. 

The  typical  and  classic  RD  is  made  up  of  the  following  characteristics  : 

Faradic  and  galvanic  inexcitability  of  the  nerve  ; 

Faradic  inexcitability  of  the  muscle  ; 

Galvanic  hypo-excitability  at  the  motor  point  with  polar  inversion  and 
slow  contraction.  As  we  shall  see,  this  apparent  galvanic  hypo-excitability 
is  due  to  inexcitability  of  the  nerve  twig  involved  at  the  motor  point ;  the 
muscle  itself  is  really  hyper-excitable,  especially  at  the  beginning  of 
the  RD. 

Of  these  three  latter  elements,  it  is  slow  contraction  that  seems  to  be 
of  greatest  importance.  Without  great  hypo-excitability  and  without 
polar  inversion,  slow  contraction  seems  sufficient  to  characterise  the  RD. 

We  must  add  to  these  characteristics  what  is  somewhat  erroneously 
called  the  displacement  of  the  motor  point  ;  this  latter  appears  no  longer  to 
have  its  seat  at  the  upper  part  of  the  muscle  but  to  be  approaching  its  lower 
insertion,  being  found  at  times  even  in  the  neighbourhood  of  its  termination 
on  the  tendon.  In  reality,  the  muscle  deprived  of  its  nerve  responds  the 
better  to  electrical  excitation  from  the  fact  that  this  latter  affects  a  greater 
part  of  the  muscular  body.  This  is  Doumer-Huet's  longitudinal  reaction, 
characterised  by  the  fact  that  the  muscle  is  more  excitable  at  the  level  of  the 
muscular  body  and  especially  in  the  neighbourhood  of  the  tendon.  This 
longitudinal  excitation  almost  always  occurs  along  the  negative  pole,  even 
when  there  is  complete  RD,  and  polar  inversion  at  the  motor  point. 

The  slowness  of  contraction  to  longitudinal  excitation  is  often  more 


46  NERVE   WOUNDS 

marked  than  to  excitation  at  the  motor  point.  It  often  persists  even  when 
excitation  at  the  motor  point  of  the  muscle,  in  process  of  recovery,  begins 
to  give  a  quick  contraction. 

The  longitudinal  excitability  of  the  paralysed  muscle  is  greater  than  that 
of  the  healthy  muscle.  This  is  one  of  the  facts  that  demonstrate  the 
hyper-excitability  of  the  paralysed  muscle  ;  its  hypo-excitability  is  but 
apparent,  resulting  from  the  inexcitability  of  the  motor  twig  supplying  it ; 
but  the  muscle  itself,  deprived  of  its  nerve,  is  really  more  excitable  than 
in  the  normal  condition.  This  galvanic  hyper-excitability  of  the  muscle 
is  often  very  marked  during  the  first  few  weeks  of  paralysis. 

It  is  also  by  longitudinal  excitation  that  we  most  easily  find  the  opening 
contraction  :  always  stronger  at  the  positive  pole,  in  contradistinction  to 
the  closing  contraction,  it  is  easy  to  provoke  only  in  cases  of  complete  RD, 
with  hyper-excitability  of  the  paralysed  muscle. 

The  reaction  of  complete  degeneration  is  generally  related  to  complete 
interruption  of  the  nerve. 

It  does  not  come  about  all  at  once,  but  within  a  fortnight  or  three 
weeks  ;  it  gradually  becomes  more  pronounced,  passing  through  all  the 
phases  ;  by  degrees  the  nerve  loses  all  excitability  ;  the  muscle  loses  its 
faradic  excitability  with  the  thick  wire  coil  and  then  with  the  thin  wire  coil, 
at  the  same  time  that  galvanic  hyper-excitability,  polar  inversion,  slow 
contraction  and  longitudinal  reaction  become  obvious. 

Nerve  regenerations,  after  complete  interruption,  act  in  exactly  the 
opposite  way.  On  examining  the  muscles,  we  find  that  galvanic  hypo- 
excitability  diminishes,  that  polar  inversion  becomes  polar  equality  and  then 
returns  to  its  normal  form  ;  slow  contraction  gradually  accelerates  ;  we 
ascertain  the  reappearance  of  faradic  sensibility  and  faradic  contraction 
with  the  thin  wire  coil,  then  faradic  contractility  with  the  thick  wire 
coil  reappears,  though  generally  tardily  and  preceded  by  the  return  of 
voluntary  contractility. 

The  nerve  also  slowly  resumes  its  normal  excitability.  As  a  rule  the 
voluntary  movements  appear  before  the  excitability  of  the  nerve. 

As  the  different  muscles  of  the  same  nerve  region  resume  their  functions 
according  as  they  are  affected  by  the  progression  of  the  regenerated  axis- 
cylinders,  we  note  the  first  signs  of  improvement  in  those  muscles  supplied 
by  the  nerve  nearest  the  origin  of  the  limb.  There  result  therefrom 
dissociations  in  the  reaction  of  degeneration. 

In  a  paralysed  muscle  we  may  also  note  the  return  of  the  normal 
reactions  in  some  muscular  fibres  at  the  upper  part  of  the  muscle,  around 
the  motor  point,  whereas  the  lower  fibres  still  present  the  RD  and  still 
respond  to  longitudinal  reaction  by  slow  contraction. 

2.  Syndromes  of  compression  or  irritation. — Reaction  of  partial 
degeneration. — The  RD  is  usually  incomplete  or  only  faintly  indicated 


ELECTRICAL    EXAMINATION  47 

if  there  is  no  nerve  interruption,  in  simple  compressions  or  in  cases  of 
moderate  nerve  irritation. 

Very  different  types  of  partial  RD  may  be  found. 

Sometimes  it  consists  of  a  simple  widespread  hypo-excitability  of  nerves 
and  muscles  to  the  faradic  and  galvanic  currents. 

At  other  times  it  consists  of  a  faradic  and  galvanic  hypo-excitability  of 
the  muscles,  along  with  inexcitability  of  the  nerve  trunks.  It  is  in  these 
cases  that  we  can  at  times  observe  the  slowness  of  the  contraction  under 
the  faradic  current. 

In  other  cases,  there  is  lacking  only  one  factor  to  the  complete  RD  : 
the  contraction  is  not  very  slow,  or  else,  whilst  slow  to  the  positive,  it  is 
quick  to  the  negative,  corresponding  to  the  slightest  forms  of  the  RD  ; 
again  it  is  the  polar  inversion  that  fails,  or  rather  it  disappears  when  we 
cross  the  threshold  of  excitation  ;  or  again  we  find  that  longitudinal  hyper- 
excitability  fails. 

3.  Syndromes  of  fibrous  transformation. — Electrical  inexcitabimty 
of  the  muscle. — In  the  complete  RD,  we  have  seen  that  galvanic  excit- 
ability was  retained;  apparently  diminished  if  we  seek  excitation  at  the 
motor  point,  but  in  reality  increased  if  we  excite  the  muscular  body  itself 
or  seek  longitudinal  reaction. 

This  excitability  of  the  muscle  may  be  seen  to  diminish  or  even 
disappear  completely,  at  all  events  with  currents  of  twenty-five  to  thirty 
milli-amperes,  the  only  ones  that  can  practically  be  utilised  in  electro- 
diagnosis. 

This  reaction  of  muscular  hypo-excitability  or  inexcitability  always 
indicates  very  profound  lesions  of  the  muscle  ;  it  shows  that  the  muscle 
has  lost  its  contractile  structure,  and  that  it  has  undergone  more  or  less  a 
process  of  infiltration  or  one  of  fibrous  transformation.  This  reaction 
is  met  with  in  certain  cases  of  long-standing  nerve  interruption  ;  it 
appears  more  quickly  in  muscles  left  untreated  by  either  massage  or 
electricity. 

Consequently  it  has  a  relatively  serious  prognosis.  It  should,  how- 
ever, be  known  that  this  muscle,  even  after  fibrous  transformation,  may 
slowly  regain  its  normal  characteristics  if  the  regenerated  axis-cylinders 
reach  it  soon  enough; 

The  syndrome  of  muscular  hypo-excitability  or  of  muscular  inexcita- 
bility is  found  with  quite  special  frequency  in  nerve  irritation,  which  so 
often  causes  fibrous  contraction  and  infiltration  of  the  muscles. 

It  is  often  superposed  on  the  RD,  emphasising,  sometimes  to  an 
enormous  degree,  the  galvanic  hypo-excitability  of  the  muscles. 

In  other  cases,  it  exists  without  the  RD,  it  is  then  characterised  by 
marked  hvpo-excitability  of  the  nerves  and  muscles  to  the  faradic  and 
galvanic  currents.  It  is  found  in  these  cases  that,  in  contradistinction  to  the 
syndrome  of  the  paralytic  partial  RD,  the  hypo-excitability  of  the  muscle 


48  NERVE   WOUNDS 

to  the  faradic  and  to  the  galvanic  currents  at  the  motor  point  is  not 
accompanied  by  the  usual  longitudinal  hyper-excitability. 

In  certain  cases,  one  may  even  ascertain  the  apparently  paradoxical 
association  of  the  following  symptoms  : 

The  nerves  and  muscles  are  almost  incapable  of  being  excited  by  the 
usual  faradic  and  galvanic  currents  ;  but  violent  faradic  shocks,  or  galvanic 
currents  at  the  motor  point  up  to  twenty-five  or  thirty  milli-amperes  produce 
rather  feeble  contractions  of  small  areas,  limited  to  a  few  muscular  fibres  ; 
we  are  surprised  to  find  that  these  contractions  are  quick,  without  polar 
inversion. 

As  Huet  has  shown,  this  reaction  after  all  has  a  relatively  favourable 
prognosis.  It  shows  that  the  muscle  has  undergone  a  more  or  less  pro- 
found fibrous  transformation,  from  lack  of  attention  or  else  from  nerve 
irritation  ;  but  at  the  same  time  it  indicates  the  persistence  of  healthy,  or 
the  arrival  of  some  regenerated  axis-cylinders  and  enables  us  to  predict  the 
slow  restoration  of  motor  functions. 

4.  Reaction  of  Exhaustion. — Sometimes  we  find  in  weakened  muscles, 
and  oftener  during  muscular  regeneration,  an  indication  of  the  reaction 
of  exhaustion  described  by  Jolly  in  myasthenia. 

The  muscle  makes  unequal  responses  to  successive  faradic  excitations, 
or  rather,  if  we  utilise  a  somewhat  rapid  faradic  rhythm,  we  find  a  con- 
traction fail  from  time  to  time  ;  there  are  "misses"  comparable  to  those 
of  cardiac  arhythmia  in  myocardial  lesions. 

In  other  cases,  if  the  muscle  is  excited  by  a  rapid  rhythm  or  a 
tetanising  current,  it  is  found  to  become  rapidly  inexcitable. 

5.  Myotonic  Reaction  — Lastly,  in  some  cases  of  slight  neuritis, 
usually  accompanied  with  contraction,  the  muscles  seem  to  be  slightly 
hyper-excitable  under  the  faradic  current  ;  tetanisation  seems  to  take  place 
with  interruptions  somewhat  less  rapid  than  in  the  normal  state,  which 
simply  shows,  after  all,  a  certain  prolongation  of  the  contraction.  This, 
however,  is  not  the  true  myotonic  reaction,  which  is  mainly  characterised 
by  a  tonic,  lasting  contraction,  persisting  after  the  cessation  of  galvanic 
excitation.  It  essentially  characterises  Thomsen's  disease  and  certain 
myopathies.  It  does  not  exist  so  clearly  in  cases  of  nerve  lesion  ;  all  the 
same,  in  recent  cases  of  paralysis  one  may  at  times  observe  a  faint  con- 
traction persisting  during  the  passage  of  the  galvanic  current.  This  is 
the  exaggerated  manifestation  of  galvano-tonus,  or  galvanic  hyper-excita- 
bility of  the  muscle,  which  exists  in  recent  RD. 

***** 
The    disturbances  of  electrical  reactions  and    the  RD    in   particular 
essentially  characterise  peripheral  paralysis,  i.e.  those  which  result — 

From  lesion  of  the  motor  cells  of  the  spinal  cord  (poliomyelitis, 
hematomyelia,  etc.)  ; 


ELECTRICAL   EXAMINATION  49 

From  lesion  of  the  anterior  roots  (inflammation  of  the  roots,  com- 
pressions, etc.)  ; 

From  traumatic  lesion  of  the  plexuses  or  peripheral  nerves  ;  from  the 
polyneurites. 

Functional,  hysterical  paralyses  and  paralyses  of  cerebral  origin  or 
resulting  from  lesion  of  the  pyramidal  tract  (upper  motor  neurone)  are 
never  accompanied  by  important  disturbances  of  the  electrical  reactions. 
At  most  there  is  slight  hypo-excitability  from  muscular  disuse. 

At  the  same  time,  in  sections  of  the  cord,  we  may  frequently  note  im- 
portant electrical  disturbances,  as  remarked  by  P.  Marie  and  Foix,  but  they 
manifestly  result  from  the  reaction  of  the  grave  medullary  lesion  on  the 
motor  cells  of  the  anterior  horns  below  the  lesion. 

Only  one  affection  is  accompanied  by  electrical  disturbances  as  profound 
and  rapid  as  those  of  the  peripheral  nerve  lesions,  this  is  ischemic  paralysis 
from  arterial  obliteration.  Still,  we  see  rather  the  syndrome  of  fibrous  trans- 
formation of  the  muscles  than  the  true  RD  ;  inexcitability  of  the  muscles 
comes  on  earlier  and  is  more  marked  than  the  inexcitability  of  the  nerve 
controlling  it. 


II.— SOME  POINTS    IN   ELECTROPHYSIOLOQY 

Modern  investigations  in  electrophysiology  now  enable  us  to  complete 
and  interpret  the  information  supplied  by  the  classical  electro-diagnosis. 
Three  important  points  stand  out  prominently  : 

1.  The  active  pole — which  is  always  the  negative  pole,  at  the  closing 
of  the  current ; 

2.  The  galvanic  hyper-excitability  of  the  muscle  deprived  of  its  nerve  ; 

3.  The  velocity  of  excitability  or  chronaxie. 

1.  Polar  Action. — It  now  seems  proved  that  the  negative  pole  alone 
is  capable  of  producing  a  closing  contraction  with  the  galvanic  current. 

Consequently,  the  contraction  obtained  by  the  positive  pole  in  the 
paralysed  muscles  and  characteristic  of  polar  inversion  of  the  RD,  is  falsely 
attributed  to  the  action  of  this  pole.  It  results  from  the  action  of  a  virtual, 
negative  pole,  appearing  deep  within  the  tissues  and  in  the  muscle  itself. 

1.  As  a  demonstration,  an  interesting  experiment  made  by  Cardot  and 
Laugier  may  be  given.* 

A  frog's  gastrocnemius  and  the  nerve  supplying  it  are  placed  in  a  small  box  made 
of  paraffin  wax,  divided  into  two  compartments  by  a  partition  traversed  by  the  nerve. 
Thus  there  are  two  separate  rooms,  the  one  for  the  muscle,  the  other  tor  the  nerve,  which 
passes  across  the  partition  and  penetrates  the  muscle. 

A  wide  indifferent  electrode  supports  the  muscle,  a  small  active  one  surrounds  the 
nerve. 


*  H.  Cardot  and  A.  Laugier.     Journal  Je  Physiologic  ct  Je  Pathologic  generate.     Paris,  1912. 

4 


5o  NERVE   WOUNDS 

Each  of  these  electrodes  may  be  made  positive  or  negative  at  will  ;  whenever  the 
current  is  established,  and  in  whatsoever  direction,  the  muscle  contracts. 

We  have  to  discover  which  is  the  active  pole,  and  upon  what  it  acts,  nerve  or  muscle. 

Now,  Lapicque  has  shown  that  the  velocity  of  excitability  or  ckronaxie  of  a  neuro- 
muscular system  varies  with  the  temperature.  Thus,  by  varying  the  temperature  of  one 
of  the  two  compartments,  the  variations  of  chronaxle  can  be  studied  and  the  problem 
solved. 

Indeed,  if  the  nerve  compartment  and  the  nerve  itself  are  brought  into  different 
temperatures,  with  the  negative  pole  we  shall  obtain  corresponding  differences  of  velocity  ; 
if,  on  the  other  hand,  we  apply  to  the  nerve  the  positive  electrode,  the  velocity  of 
excitability  remains  invariable,  whatever  the  variations  of  temperature. 

Conversely,  if  the  temperature  of  the  compartment  containing  the  muscle  is  made  lo 
vary  whilst  maintaining  the  nerve  at  a  constant  temperature,  we  find  that  only  excitation 
of  the  muscle  by  the  negative  pole  is  affected  by  the  variations  of  temperature. 

Thus  it  is  demonstrated  that  the  negative  pole  alone  is  active  at  the 
closing  of  the  current  for  nerve  and  muscle  alike,  since  the  negative 
excitation  alone  is  influenced  by  variations  of  temperature. 

It  has  also  been  shown  that,  at  the  opening  of  the  current,  the  positive 
pole  alone  is  efficacious.  But  the  opening  contraction  at  the  positive  pole 
is  usually  not  utilisable  in  electro-diagnosis.  It  requires  an  intensity  eight 
to  ten  times  greater  than  the  closing  contraction  at  the  negative  pole. 

2.  This  principle  that  the  negative  pole  alone  is  active  at  the  closing 
of  the  current  thus  seems  in  formal  contradiction  to  the  results  of  the 
electro-diagnosis  in  the  paralysed  muscles,  showing  the  existence  of  a  polar 
inversion  and  of  a  closing  contraction  at  the  positive  pole. 

An  experiment  of  Bourguignon  *  clearly  shows  that  this  contradiction 
is  but  apparent. 

Thus,  if  we  apply  a  small  active  electrode  to  a  superficial  nerve, 
close  to  muscular  bellies  independent  of  its  motor  supply  (as,  e.g.,  is  the 
musculo-spiral  nerve,  in  the  groove  of  the  biceps  or  the  median  at  the 
inner  surface  of  the  arm),  we  obtain  by  a  rather  powerful  negative  or 
positive  excitation  very  different  results. 

Excitation  of  the  nerve  by  the  negative  pole  will  produce  at  the  closing 
of  the  current  a  contraction  in  all  the  muscles  it  supplies  in  the  forearm. 

The  closing  excitation  at  the  same  point  by  the  positive  pole,  however, 
causes  no  movement  in  the  muscles  supplied  by  the  nerve.  On  the  other 
hand,  we  notice  a  contraction  in  the  neighbouring  muscles,  biceps  and 
triceps. 

Positive  excitation,  then,  has  not  taken  place  in  the  nerve  placed  in 
contact  with  the  electrode  ;  it  has,  however,  affected  a  distance  the  muscles 
next  to  this  nerve. 

It  is  therefore  proved  that  the  positive  pole  in  contact  with  the  nerve 
is  inactive.     The  motor  response,  a  distance,  of  the  neighbouring  muscles 

*    Bourguignon.      Revue  neuro/ogique,  April  30,  19 14. 


ELECTRICAL    EXAMINATION  51 

is  due  to  the  existence  of  a  virtual  negative  pole,  which  the  real  positive 
pole,  applied  to  their  surface,  causes  to  appear  in  the  neighbouring 
muscles. 

This  virtual  pole,  however,  appearing  deep  in  the  tissues,  along  the 
course  of  the  lines  of  force,  naturally  has  not  the  density  of  the  superficial 
pole  represented  by  the  small  active  electrode.  Its  action,  consequently, 
is  diffused  ;  it  falls  upon  the  mass  of  the  muscles  and  not  in  a  precise- 
energetic  fashion  on  the  motor  nerve  twig  innervating  them. 

From  these  facts,  the  following  conclusions  may  be  drawn  : — 

The  negative  pole,  at  the  closing  of  the  current,  exercises  a  direct, 
precise  and  limited  action  on  the  nerves  and  muscles  with  which  it  is  in 
contact.  Moreover,  it  causes  to  appear  deep  in  the  tissues  a  virtual 
positive  pole,  inactive  and  devoid  of  importance. 

The  positive  pole,  on  the  surface,  acts  indirectly  at  the  closing,  through 
the  virtual  negative  pole  which  it  causes  to  appear  deep  in  the  tissues. 
This  excitation,  therefore,  is  more  diffused,  indefinite  and  imperfectly 
limited  ;  having  less  density,  it  requires  a  far  greater  intensity  to  produce 
the  same  results. 

These  facts  enable  us  to  explain  the  electrical  reactions  of  a  normal 
muscle  and  of  a  paralysed  muscle. 

(a)  If  we  excite  a  healthy  muscle  at  the  motor  point,  we  rind  that  it 
contracts  at  the  closing  of  the  current,  under  the  direct  action  of  the 
negative  pole,  with  a  very  small  current  ;  for  instance,  the  threshold  is  at 
one  to  two  milli-amperes.  The  excitation  has  acted  directly,  with  great 
intensity,  on  the  motor  twig  of  the  muscle.  In  these  conditions  it  "has 
produced  the  maximum  of  useful  effect. 

At  the  same  point,  with  the  same  current,  the  positive  pole  is  altogether 
ineffective.  The  intensity  of  the  current  must  be  sensibly  increased  to 
find  the  positive  threshold,  i.e.  to  cause  to  appear  in  the  muscle  a  virtual 
negative  pole,  capable  of  producing,  in  spite  of  its  diffusion,  an  equally 
strong  excitation. 

If  the  muscle  is  excited  outside  of  the  motor  point,  at  the  level  of  the 
muscular  belly,  or  by  longitudinal  excitation,  we  at  once  see  that  greater 
intensity  is  needed  to  obtain  the  threshold  of  contraction.  For  instance, 
five,  six,  eight  milli-amperes  are  needed  to  obtain  the  contraction.  This 
is  because  excitation  no  longer  acts  directly  on  the  motor  twig  but  is 
diffused  with  less  intensity  in  the  muscle  itself. 

Again,  we  shall  see  that  the  muscle  responds  almost  as  well  and  often 
even  far  better  to  the  positive  pole.  In  this  case  it  is  excited  by  the 
virtual  negative  pole  in  its  depth. 

Thus  we  understand  why  we  may  find  in  a  healthy  muscle  false  polar 
equalities  and  false  polar  inversions,  when  the  excitation  does  not  bear 
exactly  on  the  motor  point,  or  when  the  real  motor  point  is  with  difficulty 
accessible  on  the  surface. 


52  NERVE   WOUNDS 

{l>)  In  a  paralysed  muscle  there  is  no  longer  any  real  motor  point ;  the 
nerve  twig  supplying  it  is  inexcitable. 

On  the  other  hand,  the  muscle  itself  has  retained  its  excitability  ;  we 
shall  even  see  shortly  that  this  excitability  is  usually  increased.  It  contracts, 
however,  only  under  the  influence  of  a  diffused  current,  distributed 
throughout  the  muscular  belly,  the  density  of  which  current,  consequently, 
will  be  less  great,  whilst,  in  order  to  produce  the  same  contraction  as  the 
excitation  of  the  nerve,  it  will  have  to  possess  greater  intensity. 

In  these  conditions,  the  muscle  makes  a  similar  response  when  excited 
at  the  motor  point  or  at  a  distance  from  this  point ;  by  excitation  of  the 
muscular  belly  itself  and  especially  by  its  longitudinal  excitation  we  obtain 
even  a  stronger  contraction  than  at  the  motor  point  :  this  is  the 
phenomenon  inaccurately  designated  as  the  descent  of  the  motor  point,  or 
more  correctly  the  longitudinal  reaction. 

If  the  negative  electrode  is  applied  to  the  muscle  in  its  lower  part  or 
in  the  neighbourhood  of  the  tendon,  the  current  directly  excites  the 
muscular  fibres  throughout  their  whole  length  ;  longitudinal  reaction  is 
thus  almost  always  produced  more  readily  by  the  negative  pole. 

If,  on  the  other  hand,  the  negative  electrode  is  applied  to  the  upper 
part  of  the  muscle,  near  the  motor  point,  the  muscular  fibres  are  excited 
only  partially  and  feebly  ;  if  we  use  the  positive  electrode,  it  causes  to  appear 
in  the  muscular  body  a  virtual  negative  pole,  the  action  of  which  on  the 
muscular  fibres  is  direct  and  far  more  effective  than  surface  excitation  ;  we 
obtain  polar  inversion. 

2.  Hyper-excitability  of  the  paralysed  muscles. — Galvano-tonus.- — 
Apparently  the  paralysed  muscle  is  less  excitable  under  the  galvanic 
current  than  the  healthy  muscle.     The  contrary,  however,  is  the  case. 

The  paralysed  muscle  has  lost  its  nerve  excitability,  i.e.  it  is  impossible 
to  excite  at  the  motor  point  the  nerve  twig  which  normally  responded  to 
a  very  feeble  current. 

The  muscle  itself,  however,  has  retained  its  excitability,  which  is  more 
difficult  to  provoke  than  that  of  the  nerve,  on  account  of  the  diffusion  ; 
consequently  it  requires  greater  intensity. 

This  electrical  excitability  of  the  paralysed  muscle  is  frequently  intensified, 
just  as  we  have  found  its  mechanical  excitability  intensified,  as  shown  by 
the  idio-muscular  reflexes. 

Only  after  some  time,  with  the  progress  of  muscular  atrophy,  the 
prolonged  disuse  of  the  muscle  and  the  gradual  disappearance  of  the 
contractile  structure,  do  its  electrical  and  mechanical  excitability  diminish 
and  finally  disappear. 

There  are  two  ways  of  accounting  for  this  hyper-excitability  of  the 
recently  paralysed  muscle. 

First,  by  investigating  the  threshold  in  the  neighbourhood  of  the 
motor  point ;  the  muscle  usually  responds  to  the  positive  pole. 


ELECTRICAL   EXAMINATION  53 

Polar  inversion  takes  place  and  we  find  that  the  positive  threshold  is 
often  less  raised  on  the  paralysed  muscle  than  on  the  healthy  one. 

Secondly,  we  can  more  easily  recognise  this  hyper-excitability  by 
longitudinal  excitation.  The  muscle  almost  always  responds  to  the 
negative  pole,  and  this  threshold  of  longitudinal  excitation  is  always  far 
less  raised  than  on  the  healthy  muscle. 

In  some  cases  there  is  also  seen  to  appear  the  opening  contraction 
which  is  difficult  to  obtain  on  the  healthy  muscle  with  bearable  currents. 

This  hyper-excitability  of  the  paralysed  muscle,  shown  by  longitudinal 
excitation,  is  particularly  clear  in  cases  of  recent  paralysis  ;  it  diminishes 
with  the  progress  of  the  atrophy.  It  may  even  appear  in  muscles  in- 
completely paralysed  and  thus  demonstrate  very  slight  nerve  lesions.  It 
disappears  somewhat  rapidly  as  soon  as  nerve  regeneration  manifests  itself. 
It  is  sometimes  called  galvano-tonus. 

A  therapeutic  effect  results  from  this  conception  of  the  longitudinal 
hyper-excitability  of  the  paralysed  muscle. 

It  is  logical  to  provoke  by  longitudinal  excitation  the  contractions  used 
in  galvanic  treatment  ;  they  are  fuller,  more  complete  and  easier  to  obtain 
with  feeble  currents  ;  the  method  of  longitudinal  excitation  produces  the 
maximum  of  effect  with  the  minimum  of  current. 

3.  Velocity  of  excitability. — Chronaxie. — The  conception  of  velocity 
of  excitability,  introduced  into  electrophysiology  by  Engelmann,  Dubois, 
Weiss,  Lapicque,  etc.,  has  only  of  recent  years  found  a  practical  applica- 
tion in  electro-diagnosis. 

It  is,  however,  most  important,  as  are  also  its  practical  consequences. 

I.  Velocity  of  excitability  may  be  measured  by  the  minimum  duration 
of  the  passage  of  the  galvanic  current  necessary  to  produce  the  threshold 
of  contraction  with  the  minimum  intensity  (for  an  indefinite  duration  of 
passage). 

In  order  that  a  muscle  may  contract,  there  must  be  excitation  of  the 
muscle  or  nerve  supplying  it  with  a  minimum  of  intensity  ;  this  is  the 
threshold  of  excitation. 

That  this  minimum  current,  however,  may  be  effective,  it  must  last 
some  time ;  below  this  minimum  duration  the  same  current  remains 
ineffectual  ;  if  this  duration  is  increased,  the  muscular  contraction  obtained 
at  the  opening  remains  the  same,  however  long  the  current  takes  to  pass. 

If  we  diminish  the  minimum  duration  of  the  passage  of  the  current, 
there  is  no  longer  any  contraction  by  the  liminal  current ;  contraction 
can  be  obtained  only  by  increasing  the  intensity  of  the  current. 

This  minimum  duration  of  the  liminal  current,  capable  of  determining 
the  threshold  of  excitation  indefinitely,  is  a  measure  of  the  velocity  of 
excitabilitv. 

For    practical    reasons,    most    recent    researches  have  utilised   another 


54  NERVE   WOUNDS 

measure  of  velocity  of  excitability.  First,  the  physiologists  determine 
the  threshold  of  excitation  for  a  current  of  indefinite  duration  :  this  is  the 
rheobase  or  rheobasic  threshold  of  Lapicque.  Then  we  seek  the  velocity 
of  excitability  for  a  current  twice  as  intense  as  the  rheobase.  To  this 
minimum  duration  of  passage  for  a  double  intensity  of  the  rheobase 
Lapicque  gave  the  name  of  chronaxie. 

The  minimum  duration  of  passage  for  the  liminal  current,  and 
chronaxie,  are  two  different  measures  of  the  velocity  of  excitability  ;  the 
former  is  about  ten  times  greater  than  the  latter. 

The  relation  between  duration  and  intensity  of  the  liminal  current  is 
particularly  important.  For  the  same  muscle  of  the  same  species  in 
identical  conditions  it  is  invariable. 

Consequently  it  supplies  a  mathematical  and  measurable  basis  for 
reckoning  the  excitability  of  a  nerve  or  muscle. 

It  is  also  an  extremely  sensible  method  ;  the  works  of  Lapicque  and 
his  pupils  have  demonstrated  the  considerable  variations  of  chronaxie 
according  to  the  temperature  and  the  different  physiological  and  patho- 
logical states  of  nerves  and  muscles;  the  slightest  and  most  fleeting 
injuries  of  the  nerve  twigs  are  shown  by  considerable  modifications  of 
chronaxie  ;  the  traction  of  a  nerve  trunk,  its  slight  compression,  the  action 
of  cocaine,  ether,  chloroform,  etc.  ;  are  immediately  revealed  by  variations 
of  the  velocity  of  excitability,  corresponding  to  fleeting  modifications  of 
the  structure  of  the  nerve.    (  Lapicque  and  Legendre.  ) 

In  spite  of  its  importance,  however,  the  fact  of  chronaxie  has  long 
enough  eluded  the  researches  of  observers,  for  the  durations  of  passage 
to  be  studied  are  extremely  short.  We  may  see  this  when  we  reflect 
that  chronaxie  of  the  frog's  gastrocnemius  muscle,  for  instance,  at  a 
temperature  of  150,  is  about  three  ten-thousandths  of  a  second. 

In  man,  we  shall  see  that  we  may  reckon  at  about  or  even  below  one- 
thousandth  of  a  second  chronaxie  of  the  normal  muscle  ;  its  chronaxie  is 
rapid  :  the  paralysed  muscle,  on  the  other  hand,  easily  reaches  forty,  fifty, 
sixty  thousandths  of  a  second  ;  thus  it  is  excitable  only  by  a  relatively  pro- 
longed current  :  its  chronaxie  is  slow.  The  difference  is  seen  to  be  great  ; 
nevertheless  the  results,  even  approximate,  given  by  the  different  methods 
of  research,  are  of  considerable  value. 

***** 

The  application  of  these  facts  to  electro-diagnosis  has  hitherto  en- 
countered many  difficulties,  mainly  resulting  from  the  resistance  of  the 
skin  and  from  the  extreme  variability  of  muscular  excitability  applied 
through  the  integuments. 

Three  processes  have  been  advanced  for  reckoning  the  velocity  of 
excitability  :  First,  two  indirect  processes,  that  of  Cluzet  by  discharges  of 
condensers  ;  that  of  Bourguignon  and  Laugier  by  comparison  of  faradic 
excitability  at  the  opening  and  closing  of  the  induced  current ;  second,  a 


ELECTRICAL   EXAMINATION  55 

direct  process,  recommended  by  Lapicque,  the  simplification  of  the 
methods  utilised  in  electrophysiology  for  measuring  the  duration  of  a  very 
short  galvanic  current. 

(a)  Discharges  of  Condensers  (Cluzet).* — Condensers  of  different 
capacity,  but  of  the  same  voltage,  discharge  themselves  according  to  a 
duration  proportional  to  their  capacity. 

According  to  their  capacity  they  may  supply  currents  of  variable 
duration. 

It  will  be  sufficient  first  to  produce  the  voltage  corresponding  to  the 
threshhold  of  contraction  for  an  indefinite  current  (rheobasic  voltage). 
Then,  if  the  condensers  are  charged  at  the  same  voltage,  or  rather  at  double 
the  rheobasic  voltage,  we  have  only  to  find  out  the  feeblest  of  the  con- 
densers capable  of  producing  contraction.  The  measure  of  capacity  of 
this  condenser  gives  the  duration  of  the  discharge,  consequently  the  velocity 
of  excitability. 

Practically,  this  method,  of  which  we  have  simply  set  forth  the  barest 
schematic  data,  involves  a  certain  number  of  difficulties  arising  mainly 
from  cutaneous  resistance  which  varies  according  to  the  intensity  of  the 
current  and  even,  in  the  case  of  a  current  of  constant  intensity,  according 
to  the  duration  of  this  current.  We  shall  find  these  same  difficulties  in 
all  the  methods  proposed. 

The  results  obtained,  therefore,  constitute  only  approximations  ;  never- 
theless they  are  sufficiently  precise  to  reveal  the  slightest  lesions  and  enable 
them  to  be  expressed  in  figures,  the  value  of  which,  relative  though  it  be, 
is  nevertheless  great. 

(/;)  The  Process  of  Bourguignon  and  Laugier. — Relation  between 
the  Induced  Waves  of  Opening  and  Closing. — It  is  well  known  that 
in  an  induction  coil,  when  the  primary  current  (inductor)  is  closed,  there 
is  induced  in  the  secondary  a  current  in  the  opposite  direction  ;  on  the 
opening  of  the  primary  current  there  arises  in  the  secondary  a  current  of 
the  same  direction  as  the  inductor  current. 

These  two  induced  waves,  of  closing  and  opening,  have  not  the  same 
characteristics.  Their  direction  is  inverse,  but  this  is  of  no  great  import- 
ance. On  the  other  hand,  they  are  unequal  in  duration  and  intensity  ; 
this  gives  them  a  different  physiological  action. 

In  the  induced  waves  of  closing  and  opening,  naturally,  the  quantity 
of  induced  electricity  is  equal.  The  closing  wave,  however,  is  long,  con- 
sequently its  intensity  is  less  ;  the  wave  of  opening  is  short,  and  its  intensity 
is  greater. 

This  difference  results  from  the  way  in  which  the  current  is  set  up  ; 
the  closing  current  of  the  primary  started   in  the  induction  coil  is  set   up 

*   Cluzet.       Lyon    Medical,    26     November,     191  I  ;    Journal   dt    Radiologic    ft    a"E/cctro/ogiet 
March  1914. 


56  NERVE   WOUNDS 

slowly,  because  of  self-induction.     The  primary  closing  current  and   the 
resulting  induced  current  are  consequently  prolonged  and  slowed  down. 

On  the  other  hand,  at  the  opening  of  the  primary,  no  resistance  of 
self-induction  takes  place,  the  wave  resulting  therefrom,  both  in  the 
primary  and  in  the  induced,  is  short,  almost  instantaneous  even,  if  care 
has  been  taken  to  extinguish  the  rupture  spark  which  tends  slightly  to 
lengthen  the  opening  wave. 

In  the  induction  coils  usually  employed  in  faradic  excitation,  only  the 
opening  wave,  short  and  intense,  is  efficacious.  The  shortness  of  this  wave 
explains  why  it  is  capable  of  exciting  only  the  normal  muscle,  with  rapid 
chronaxie.  It  is  ineffective  in  the  paralysed  muscle,  with  slow  chronaxie, 
unless  its  voltage  is  enormously  increased  by  using  an  induction  coil  of 
adequate  electro-motive  force  and  considerable  sheathing.  This  explains 
the  contractions  sometimes  obtained  in  paralysed  muscles  by  thin  wire 
coils  (usually  of  800  ohms).  With  a  coil  of  1600,  1800,  and  even  3000 
ohms,  we  can  almost  always  obtain  contraction  of  a  paralysed  muscle,  but 
the  intensity  is  very  great  and  the  excitation  painful. 

On  the  other  hand,  the  opening  wave  is  long,  consequently  it  is  capable 
both  of  exciting  normal  muscles  with  rapid  chronaxie  and  degenerated 
muscles  with  slow  chronaxie. 

Thus,  with  the  same  coil,  an  adequately  powerful  one,  we  have  two 
waves  of  unequal  though  constant  duration,  a  short  wave  and  a  long  one. 

Let  us  first  produce  the  threshold  of  excitation  with  the  short  opening 
wave,  and  note,  by  the  sheathing  of  the  coil,  the  intensity  necessary  for 
contraction.  A  healthy  muscle,  with  rapid  chronaxie,  contracts  with  the 
short  wave  as  soon  as  it  reaches  the  rheobasic  threshold  with  extremely 
small  sheathing.  A  paralysed  muscle,  with  slow  chronaxie,  will  contract 
with  the  short  wave  only  if  it  attains  a  far  greater  intensity,  much  superior 
to  the  rheobasic  threshold  with  considerably  greater  sheathing. 

Afterwards  let  us  produce  the  threshold  of  excitation  with  the  long 
closing  wave.  The  healthy  muscle  will  again  contract  when  the  rheobasic 
threshold  has  been  reached  ;  given  the  less  intensity  of  the  closing  wave 
by  reason  of  its  longer  duration,  there  will  be  needed  a  greater  sheathing 
of  coil  than  for  the  opening  wave,  usually  almost  double.  The  paralysed 
muscle,  with  slow  chronaxie,  will  also  be  contracted  by  the  long  wave, 
when  the  threshold  of  excitation  has  been  reached  ;  i.e.,  with  an  intensity 
somewhat  higher  than  that  of  the  healthy  muscle  and  a  scarcely  greater 
sheathing. 

In  a  word,  for  the  healthy  muscle,  between  the  sheathing,  conse- 
quently between  the  intensity  of  the  opening  and  closing  thresholds,  there 
is  a  considerable  divergence,  explained  by  the  smaller  efficacy  of  the 
closing  wave  ;  in  the  case  of  the  paralysed  muscle  the  difference  is  consider- 
ably diminished,  because  owing  to  its  slow  chronaxie  the  paralysed  muscle 


ELECTRICAL    EXAMINATION  57 

requires,  along  with  the  short  opening  wave,  a  comparatively  far  greater 
intensity. 

If  we  reduce  to  quantities  (micro-coulombs,  measured  by  the  ballistic 
galvanometer),  the  value  of  the  currents  employed,  we  are  able  to  establish 
a  real  indication,  almost  constant  for  one  and  the  same  coil,  of  the  excita- 
bility of  healthy  muscles. 

The  lowering  of  the  index  gives  the  diminution  of  the  constant  of 
excitability  of  the  muscle. 

Below  we  offer  an  example,  taken  from  Laugier. 

Case  of  musculo-spiral  paralysis  from  compression.     Examination  of  the 
extensor  carpi  ulnaris. 


OPENING    (SHORT    WAVE). 

Distance  of  coils.  Quantities. 

Heathy  side  .  .  .     14*375  cm.  or   27*5  mi- 
cro-coulombs. 
Paralysed  side.  .    10*75  cm«  or  9^  micro- 
coulombs. 


CLOSING  (LONG    WAVE). 

Distance  of  coils.  Quantities. 

7-75  cm.      or  288  micro-coulombs. 

6  cm.            or  431  micro-coulombs. 


The    index  of  excitability  determined   by  the    relation    between  the   opening  and 

closing  amounts  is  respectively  : — 

TT     ,  .        .  .        288  micro-coulombs  ,  r  .       .         .,  .        , 

Healthy  side     ,  or  10*5  normal  figure  tor  the  coil  employed. 

27-5 

Paralysed  side — ,  or  4-4. 

As  we  see,  this  indirect  method  of  reckoning  the  velocity  of  excitability 
may  give  tolerably  accurate  results.  It  enables  us  to  follow  mathematically 
the  entire  evolution  of  a  paralysed  muscle. 

Two  things  may,  however,  be  brought  against  it. 

First,  it  supplies  only  relative  figures  ;  the  constant  varies  according  to 
the  coil  employed  ;  the  constants  of  each  coil  must  be  determined  and  an 
examination  made  always  with  the  same  instrument. 

Then,  too,  it  is  rather  complicated  ;  the  main  difficulty  arises  from  the 
fact  that  at  the  intensities  at  which  the  closing  contraction  manifests  itself, 
the  opening  contraction  is  violent  and  practically  unbearable.  It  is  con- 
sequently necessary  to  eliminate  it  carefully  either  by  working  the  inter- 
ruptor  by  hand  or  by  utilising  Bourguignon's  special  interrupter  enabling 
one  to  eliminate  at  will  the  opening  contraction. 

(<:)  Lapicque's  Chronaximetre. — Lapicque  recently  issued  the  model  of 
a  simplified  chronaximetre*  for  clinical  use. 

This  is  a  "rotatory  mechanical  rheotome,  to  which  movement  is  communicated  by  ;i 
suitable  heavy  weight   falling  from  a   moderate   height  and   carrying  a  light  shaft    by 

*  L.  Lapicque.  Academe  des  Sciences,  Comptes  rendus,  t.  clxi,  p.  643,  seance  du  22  Novembre, 
1915. 


58  NERVE   WOUNDS 

a  wire  placed  over  a  pulley  with  decreasing  radius  ;  a  pointer  fixed  perpendicularly  on 
this  shaft  describes  a  circle  at  a  velocity  increasing  as  the  square  of  the  time  :  in  this 
way,  I  have  obtained  at  the  end  of  the  first  turn,  which  alone  can  be  used,  an  angle  of 
7°  to  8°  per  thousandth  of  a  second.  Two  specially  made  interrupters,  worked  in 
succession  by  the  passage  of  the  pointer,  give  clearly  and  securely  (as  experience  has 
shown)  current  durations  that  can  be  regulated  from  a  fraction  of  a  thousandth  of  a 
second  up  to  a  tenth  of  a  second.'1 

It  suffices  first  to  determine  the  threshold  of  excitation  to  closing  of 
the  negative,  for  a  current  of  indefinite  duration.  This  is  the  well-known 
negative  threshold  of  electro-diagnosis  ;  the  rheobase  of  the  physiologists. 
Then  we  must,  with  the  same  current  though  of  definite  duration 
measured  by  the  chronaximetre,  try  to  find  the  minimum  time  necessary 
for  obtaining  contraction.  This  duration  supplies  directly  the  velocity  of 
excitability. 

We  must  remember  that  physiologists  prefer  to  take  as  their  starting 
point  a  double  intensity  of  the  rheobase. 

That  we  may  avoid  too  short  durations,  it  is  preferable  in  clinical 
electro-diagnosis  to  seek  chronaxie,  starting  with  the  rheobase  itself. 

Perhaps  the  results  are  somewhat  less  precise,  but  the  durations  are 
longer  and  easier  to  reckon. 

The  variations  in  chronaxie  revealed  by  this  method  between  the  healthy 
muscle  and  the  paralysed  muscle  are  enormous.  Whereas  a  healthy  muscle 
contracts  at  one  to  two  thousandths  of  a  second,  and  often  far  below  one 
thousandth,  chronaxie  of  a  paralysed  muscle,  manifesting  the  RD,  easily 
rises  to  forty,  sixty  thousandths  of  a  second,  and  even  more. 

This  difference  is  less  easy  to  estimate  than  the  delay  and  slowness  of 
galvanic  contraction,  which,  after  all,  are  but  the  objective  expression  of  the 
same  phenomenon. 

Without  claiming  the  precision  of  an  apparatus  in  physics,  the 
chronaximetre  enables  us  to  estimate  chronaxie  of  a  muscle  with  tolerable 
rapidity  ;  to  reckon  its  degree  of  excitability  and  to  follow  by  successive 
measurements  its  entire  pathological  evolution. 

Nevertheless,  it  must  be  confessed  that  these  researches,  even  simplified, 
are  always  too  prolonged  ;  several  hours  are  often  necessary  for  the 
methodical  examination  of  the  muscles  of  a  single  patient. 

Muscles,  too,  in  a  state  of  prolonged  inactivity,  show  a  sensible  diminu- 
tion in  their  velocity  of  excitability.  We  readily  obtain  figures  of  eight 
and  ten  thousandths  of  a  second  in  cases  of  hysterical  paralysis  or  on  the 
inactive  antagonists  of  the  paralysed  muscle. 

4.  Selective  excitation  of  paralysed  muscles. — A  second  important 
application  of  the  idea  of  chronaxie  has  been  proposed  by  Lapicque. 

In  electro-diagnosis  we  are  considerably  impeded  by  contraction  of  the 
antagonistic  muscles  excited  by  diffusion.  We  may  eliminate  this  contrac- 
tion of  the  antagonistic  muscles  which  have  remained  normal  and  limit 
excitation  to  the  paralysed  muscles  alone  by  utilising  a  progressive  current. 


ELECTRICAL    EXAMINATION  59 

In  1907-1908  Lapicque  showed  that  if  a  current  increases  gradually  to 
a  constant  intensity,  the  diminution  of  efficacy  resulting  from  this  retarda- 
tion is  smaller  in  proportion  as  chronaxia  is  slower. 

When  we  are  at  the  threshold  of  excitation,  or  even  a  little  above,  if 
the  galvanic  current  gradually  attains  its  constant  intensity,  in  six  or  eight 
thousandths  of  a  second,  for  instance,  the  normal  muscles  and  nerves,  with 
small  short  chronax'ie,  undergo  no  excitation  whatsoever.  The  degenerated 
muscles,  with  slow  chronaxie^  on  the  other  hand,  are  excited  by  a  progressive 
current,  even  if  this  current  reaches  its  intensity  only  in  fifty  or  one 
hundred  thousandths  of  a  second. 

We  need  then  only  introduce  the  current  by  degrees  in  order  to  limit 
contraction  to  the  paralysed  muscles  alone. 

Lapicque  produced  this  retardation  by  using  condensers,  placed  in 
series.  A  condenser  of  two  microfarads  causes  the  current  to  take  about 
six  thousandths  of  a  second  to  reach  95%  of  its  constant  intensity.  By 
progressively  introducing  greater  capacities,  up  to  ten,  twenty,  thirtv 
microfarads,  if  the  hypo-excitability  of  the  paralysed  muscle  necessitates 
the  use  of  a  more  intense  current,  we  finally  suppress  altogether  the  con- 
traction of  the  healthy  muscles,  without  in  any  way  modifying  the  efficacy 
of  the  current  in  the  paralysed  muscle. 

The  same  observation  is  of  considerable  importance  in  electrotherapy. 
Indeed,  it  is  necessary  to  limit  to  the  paralysed  muscles,  as  far  as  possible, 
the  contractions  provoked  by  the  current. 

By  utilising  currents  progressively,  we  shall  do  away  with  the  contrac- 
tions produced  in  the  healthy  muscles,  and,  without  any  pain,  can  utilise 
greater  intensities. 

This  is  obtained  progressively  with  special  interrupters,  with  metallic 
vibrators,  or  with  immersion  vibrators  (Bergonie,  Bordier,  etc.)  the  use  of 
which  has  recently  been  highly  recommended. 


CHAPTER    IV 
CLINICAL  TYPES 

The  most  important  and  difficult  problem  to  solve  in  peripheral  paralysis 
is  that  of  the  nature  of  the  lesion.  This  diagnosis  requires  surgical  inter- 
vention or  abstention  ;  it  enables  us  to  form  a  prognosis  as  to  the  future  of 
the  paralysis. 

The  minute  study  of  the  many  cases  of  peripheral  paralysis,  undertaken 
since  the  outbreak  of  war  in  the  various  neurological  centres,  enables  us  to 
differentiate  a  certain  number  of  clinical  syndromes  relating  to  various  nerve 
lesions  and  involving  diametrically  opposed  therapeutic  solutions. 

Along  with  J.  and  A.  Dejerine  and  Mouzon  we  may  describe  four 
syndromes  that  are  fundamental,  typical  and  clearly  characterised  : 

Syndrome  of  interruption  ; 
Syndrome  of  compression  ; 
Syndrome  of  irritation  ; 
Syndrome  of  regeneration. 

To  these  must  be  added  dissociated  syndromes  resulting  from  partial 
lesions  of  the  nerve,  and  also  complex  syndromes  produced  by  association  in 
the  same  nerve  of  two  or  more  of  the  preceding  syndromes,  in  connection 
with  the  different  or  unequal  lesions  of  the  various  fasciculi  of  which  it  is 
composed. 

We  may  also  add  the  syndrome  of  ascending  neuritis,  which  is  rather  a 
complication  than  a  consequence  of  nerve  lesions. 

In  reality,  however,  the  clinical  manifestations  of  nerve  lesions  are  even 
more  varied  and  numerous  than  this  enumeration  suggests.  A  study 
of  nerve  wounds  enables  us  continually  to  group  new  categories  and 
distinguish  new  symptomatic  forms.  Irritation  of  the  nerve  trunks,  in 
particular,  direct  or  even  ascending,  is  indicated  in  many  different  clinical 
pictures,  sometimes  by  simple  neuralgia,  sometimes  by  violent  pains,  of  a 
character  special  to  the  causalgia  of  Weir  Mitchell  ;  sometimes  by  trophic 
disturbances  which  especially  characterise  neuritic  forms,  and  sometimes 
even  by  states  of  muscular  hypertonia  which  come  under  the  heading  of 
contracture. 

Consequently,  we  shall  have  to  dwell  at  some  length  on  the  manifesta- 
tions of  nerve  irritation  and  the  polymorphous  symptoms  it  may  call  forth. 


CLINICAL   TYPES  61 


1.— SYNDROME  OF  INTERRUPTION 

The  syndrome  of  interruption  occurs  in  cases  of  complete  section  of  the 
nerve,  in  very  severe  compression,  in  tearing  or  bruising  of  the  nerve  with 
the  formation  of  a  fibrous  cicatrix. 

In  all  these  cases,  there  is  complete  interruption  of  the  nerve  fibres  ; 
their  peripheral  segment,  from  the  lesion  on  to  the  termination  of  the  fibres, 
undergoes  Wallerian  degeneration  and  gradually  disappears  ;  their  central 
segment,  above  the  lesion,  remains  almost  intact.' 

In  favourable  conditions,  such  lesions  are  capable  of  spontaneous 
regeneration.  This  will  come  about  by  a  progressive  growth  of  the  axis- 
cylinders  of  the  central  end,  which,  crossing  the  obstacle,  will  slowly  advance 
in  the  empty  sheaths  of  the  peripheral  segment  and  end  by  completely 
reconstructing  and  regenerating  the  original  nerve. 

But,  on  the  other  hand,  the  obstacle  is  frequently  insurmountable  to 
the  regenerating  fibres  ;  the  segments  of  the  sectioned  nerve  are  not  in 
contact,  compression  is  too  great,  the  cicatricial  mass  is  formed  of  too 
dense  fibrous  tissue.  In  all  these  cases,  the  regenerating  fibres  springing 
from  the  central  end  will  be  unable  to  join  the  peripheral  empty  sheaths 
which  serve  them  as  conductors,  they  will  group  themselves  at  the  level 
of  the  obstacle,  forming  a  neuroma,  or  else  will  stray  about  in  the 
neighbouring  cicatricial  tissue. 

Thus,  complete  interruptions  often  call  for  surgical  intervention  : 
either  decompression  in  certain  cases,  or,  more  frequently,  nerve  suture 
after  resection  of  the  injured  segment.  This  intervention  has  no  other 
object  than  the  removal  of  the  obstacle  and  the  placing  of  the  central  and 
peripheral  segments  in  contact  with  each  other,  so  as  to  allow  of  easy 
regeneration. 

The  syndrome  of  interruption  is  characterised — 

i.  By  immediate,  complete,  absolute  and  invariable  paralysis  of  the 
muscles  supplied  by  the  interrupted  nerve. 

2.  By  a  progressive  and  particularly  rapid  disappearance  of  muscular 
tone,  culminating  in  complete  muscular  hypotonia.  It  precedes  atrophy, 
which  occurs  more  slowly. 

3.  By  well-marked  progressive  and  regular  muscular  atrophy. 

In  spite  of  hypotonia  and  atrophy,  the  idio-muscular  reflexes  are 
intensified,  for  a  very  long  time  at  least,  whereas  the  tendon  reflexes  are 
abolished.  There  is  increase  of  mechanical  contractility  of  the  paralysed 
muscle. 

4.  By  a  reaction  of  degeneration  which  is  gradually  set  up  in  about 
two  or  three  weeks  and  culminates  in  the  complete  classical  RD. 

From  the  outset  the  nerve  excited  above  the  lesion  no  longer  transmits 
any  excitation  to  the  muscles  which  it  supplies. 


62 


NERVE   WOUNDS 


For  some  days  after  the  wound  the  nerve  remains  excitable  below  the 
lesion,  then  it  rapidly  loses  all  excitability. 

The  muscles  also  lose  in  a  few  days  their  faradic  contractility  (with 
the  thick  wire  coil),  then,  much  later,  after  a  month  or  even  more,  their 
faradic  excitability  with  the  thin  wire  coil  (the  usual  coils). 

At  the  same  time  we  have  the  disappearance  of  the  motor  point, 
polar  inversion  and  longitudinal  hypo-excitability.  Galvanic  contraction 
becomes  slow,  its  appearance  is  retarded  and  its  execution  slackened. 

5.  By  immediate,  complete  and  invariable  anaesthesia  in  the  region 
supplied  by  the  paralysed  nerve. 

Anaesthesia  is  a  little  more  widely  spread  the  first  few  days  ;  its  area 
gradually  diminishes  for  some  weeks  owing  to  anastomotic  substitutions  ; 

then  it  remains  definite  and  fixed.  Ac- 
cording to  the  case,  it  is  somewhat  variable 
in  its  characters  ;  in  principle,  it  is  abso- 
lute, involving  all  the  superficial  and  deep 
sensibilities,  though  this  is  true  only  for 
large  areas  of  anaesthesia. 

Deep  anaesthesia,  indeed,  is  always,  by 
reason  of  anastomotic  substitutions,  much 
less  widely  extended  than  superficial 
anaesthesia  ;  it  is,  on  the  other  hand, 
evoked  by  very  slight  cutaneous  pressure  : 
when  the  patient  is  pricked  with  a  needle, 
and  he  feels  simply  the  contact  not  the 
prick,  this  is  because  deep  sensibility  is 
involved.  In  the  exploration  process 
with  the  pin  which  we  have  recommended, 
the  answer  "  touch "  applies  mainly  to 
deep  sensibility. 

In  these  conditions,  when  the  anaes- 
thetised region  is  not  very  extensive,  deep  anaesthesia  is  never  complete  ; 
the  pressure  of  the  pin  is  everywhere  felt,  the  feeling  of  pain  alone  is 
abolished,  and  we  have  simple  hypo-aesthesia. 

6.  By  the  absence  of  spontaneous,  or  induced  pains  by  pressure 
on  the  nerve  and  the  muscular  bellies.  Not  only  are  the  muscles  not 
painful,  but,  as  Dejerine  has  remarked,  they  are  quite  insensitive  to 
pressure. 

The  nerve  lesion  itself  is  alone  somewhat  painful. 

7.  By  the  absence  of  formications  caused  by  pressure  on  the  nerve 
below  the  lesion. 

On  the  other  hand,  we  notice  at  the  level  of  the  lesion  a  focus  of 
formications  produced  ;  they  appear  in  a  very  limited  zone  which  corre- 
sponds to  the  neuroma  of  the  central  end.  The  fixity  of  this  zone,  for 
weeks  and  months,  is  an  important  sign  of  complete  interruption. 


1  2 

Fig.  21. — Example  of  fixed  anaes- 
thesia in  complete  interruptions. 
Section  of  the  sciatic  in  middle 
part  of  thigh.  1.  Examination 
on  the  1 6th  June,  191 5,  six  weeks 
after  the  wound.  2.  Examination 
on  the  9th  October,  1 9 1 5. 


CLINICAL   TYPES  63 

It  must  be  remembered  that  formication  appears  as  a  rule  only  about 
the  fourth  or  sixth  week,  and  that  it  disappears  in  the  end. 

8.  By  the  absence  of  trophic  disturbances,  except  occasionally  slight 
oedema,  a  little  cyanosis  and  moderate  hypertrichosis. 

Serious  trophic  disturbances,  cutaneous  sclerosis,  aponeurotic  contrac- 
tions, tendon  and  synovial  adhesions,  affections  of  the  nails,  arterial  lesions, 
do  not  belong  to  the  syndrome  of  complete  interruption. 

Still,  one  may  meet  with  trophic  ulcers,  which  are  always  secondai  v 
to  a  cutaneous  injury  ;  these  are,  for  instance,  plantar  ulcers  produced 
by  walking,  sores  on  the  great  toes  or  the  dorsal  surface  of  the  foot 
occasioned  by  the  foot-wear  ;  ulcers  on  hand  or  fingers  appearing  as 
the  result  of  a  burn,  an  excoriation,  or  even  at  times  a  simple  galvanic 
bath.  After  all,  these  are  always  accidental  ulcers,  favoured  and  pro- 
longed by  malnutrition  of  the  tissues  in  the  region  of  the  interrupted 
nerve. 

From  this  schematic  description  we  conclude  that — 

(<?)  Several  of  the  signs  characterising  the  syndrome  of  interruption, 
such  as  the  RD,  atrophy,  hypotonia,  formication,  etc.,  only  come  about 
gradually  and  after  a  certain  time. 

(l>)  Fixity  of  the  symptoms  is  one  of  the  important  characteristics  of 
the  syndrome  : 

Fixity  of  paralysis  ; 

Fixity  of  anaesthesia  ; 

Fixity  of  the  RD  ; 

Fixity  of  formication. 

(c)  Complete  interruption  of  the  nerve  fibres  does  not  altogether 
exclude  the  possibility  of  their  spontaneous  regeneration  without  surgical 
intervention. 

Consequently  it  is  absolutely  necessary  to  make  a  number  of  successive 
examinations  at  intervals  of  several  weeks  before  making  a  formal  diagnosis 
and  deciding  upon  surgical  intervention. 


II.— SYNDROME    OF   COMPRESSION 

Simple  compression  of  the  nerve  takes  place  when  the  nerve  fibres 
undergo  lesions  of  such  a  nature  that  the  voluntary  nervous  impulse,  as 
well  as  the  electric  current,  cannot  pass,  but  without  there  being  destruc- 
tion of  the  axis-cylinder  or  centrifugal  degeneration. 

In  a  word,  we  have  here  a  local  disorganisation  which  momentarily 
causes  to  disappear  the  physiological  conductivity  of  the  nerve  fibre;  but 
this  fibre  is  not  dead  ;  its  peripheral  segment  is  not  degenerated  ;  it  is 
capable,  after  the  disappearance  of  the   injury,  of  being  reorganised   and 


64  NERVE   WOUNDS 

resuming  its  functions  fairly  rapidly.  This  is  the  syndrome  produced  in 
the  momentary  compressions  of  a  nerve  ;  its  classical  example  is  musculo- 
spiral  paralysis,  called  "  a  frigore,"  produced  by  compression  of  the  nerve 
during  deep  sleep. 

Sometimes  this  syndrome  is  found  in  the  permanent  compression  of  a 
nerve  surrounded  by  a  fibrous  cicatrix  or  encased  in  callus,  but  without 
marked  narrowing. 

In  these  cases,  however,  permanent  compression,  compatible  for  a 
considerable  time  with  anatomical  survival  of  the  nerve,  may  finally 
induce  its  progressive  degeneration  ;  consequently,  we  may  find  a  syndrome 
of  compression  being  transformed  into  one  of  interruption. 

On  the  other  hand,  the  same  injury  may  induce  destruction  of  a  certain 
number  of  more  fragile  nerve  fibres  and  simple  compression  of  the  rest. 
This  results  in  a  mixed  and  very  usual  syndrome,  one  of  incomplete  inter- 
ruption, where  the  symptoms  of  interruption  are  never  fully  seen,  and 
where,  nevertheless,  we  observe  progressive  regeneration,  far  slower  than 
simple  restoration  of  a  compressed  nerve. 

The  syndromes  of  momentary  compression  must  be  compared  with 
the  fleeting  paralyses  which  often  succeed  grave  injuries  of  the  limbs,  and 
which  have  been  described  as  a  kind  of  stupor  of  the  nerves  :  these 
paralyses  disappear  after  a  few  days,  generally  without  any  disturbance  of 
electrical  reactions  revealing  the  tiny  contusions  or  the  state  of  shock  in 
the  nerve  trunk. 

The  syndrome  of  compression  is  characterised — 

1.  By  more  or  less  complete  paralysis,  generally  as  complete  as  in  the 
syndrome  of  interruption,  more  rarely  partial  and  permitting  of  a  few  ill- 
defined  movements. 

2.  By  muscular  atrophy,  far  more  rapid  and  less  intense  than  in 
complete  interruption. 

This  atrophy  may,  however,  become  very  intense,  if  compression 
persists. 

3.  By  relative  preservation  of  muscular  tone  which  is  one  of  the  best 
signs  of  simple  compression. 

Still,  one  may  also  find  muscular  tone  disappearing  after  a  time  ;  this 
muscular  atony,  however,  requires  months,  whereas  it  takes  only  a  few 
weeks  in  complete  interruption. 

The  idio-muscular  reflexes  are  almost  always  intensified  ;  if  they  are 
normal  it  shows  that  the  compression  is  very  slight. 

4.  By  a  reaction  of  partial  and  always  incomplete  degeneration,  far 
slower  in  taking  place  ;  unless  we  have  progressive  interruption  oi  the 
compressed  fibres. 

It  is  in  slight  compressions,  particularly  in  musculo-spiral  paralysis  from 
temporary  compression,  that  we  may  find  the  paradoxical  electrical 
reactions  we  have  already  mentioned  :  nerve  and  muscles  remain  more  or 


CLINICAL   TYPES 


65 


less  excitable  by  the  faradic  current  below  the  lesion,  whilst  electrical 
stimulation  of  the  nerve  above  the  lesion  causes  no  movement  whatsoever 
in  the  paralysed  region. 

5.  By  anaesthesia,  variable  in  intensity  and  extent  ;  in  general  it  is  far 
more  reduced  and  less  pronounced  than  the  anaesthesia  of  interruption  ;  in 
any  case  it  has  no  invariable  fixity. 

6.  By  the  absence  of  pains  at  the  level  of  the  lesion,  as  also  of  pains 
in  the  course  of  the  nerve  or  on  pressure  of  the  muscular  bellies  ;  these 
latter,  however,  may  retain  their  normal  sensibility  to  pressure. 

7.  By  the  absence  of  formication.  This  is  altogether  absent  in  simple 
and  transitory  compressions,  as  is  musculo-spiral  paralysis  a  frigore.  If 
we    find,    in    some    cases    of   close    and    prolonged    compression,    slight 


Fig.  22. — Attitude  of  the  hand  in  a  case  of  simple  compression  of  the  musculo-spiral 
nerve.  The  paralysis  is  the  same  as  in  cases  of  complete  interruption,  but  the  tone 
retained  gives  the  hand  a  less  drooping  posture,  one  more  resembling  that  ot  repose. 
Freeing  of  the  nerve.  First  indication  of  movement  15  days  after  intervention. 
(J.  and  A.  Dejerine  and  Mouzon,  Presse  Medicate,  18  May,  19 15.) 


formication  of  the  nerve  trunk  under  pressure,  it  indicates  the  destruction 
and  the  consecutive  regeneration  of  some  nerve  fibres.  In  a  word  it  is  a 
case  of  incomplete  interruption. 

Whilst  regeneration  of  the  few  interrupted  fibres  is  taking  place,  we 
find  the  zone  of  formication  extending  over  the  tract  of  the  nerve  below 
the  lesion,  signifying  the  progressive  advance  of  the  axis-cylinders. 

In  other  cases,  the  zone  of  induced  formication  remains  fixed,  limited 
to  the  level  of  the  lesion.  It  is  then  to  be  feared  that  the  constriction  ot 
the  nerve,  too  great  to  allow  of  the  passage  of  the  regenerating  fibres,  will, 
in  the  long  run,  cause  destruction  of  the  fibres  that  have  remained  healthy. 

8.  The  absence  of  trophic  disturbances  is  even  clearer  in  com- 
pression than  in  complete  interruption.  Usually  we  do  not  find  in  them 
the  cyanosis  and  the  slight  oedema  which  may  accompany  the  preceding 
type. 


66  NERVE   WOUNDS 

The  syndrome  of  compression,  like  that  of  interruption,  includes  a 
certain  number  of  characters  noticed  during  the  evolution  of  the  symptoms 
and  obtained  by  successive  examinations. 

Only  after  a  few  weeks'  observation  can  one  judge  of  the  necessity 
for  surgical  liberation. 

Moreover,  the  results  of  liberation  are  somewhat  variable.  In  simple 
compressions  we  often  find  that  the  nerve  regains  in  a  few  weeks, 
sometimes  a  few  days,  the  whole  of  its  functions. 

In  compression  with  incomplete  interruption,  the  duration  of  restora- 
tion is  evidently  proportional  to  the  nerve  destruction. 

The  fibres  momentarily  or  slightly  compressed  present  only  segmentary 
lesions,  i.e.,  limited  to  the  affected  point,  and  are  not  accompanied  by 
degeneration  of  the  peripheral  segment.  They  need  only  undergo  local 
restoration  for  the  nerve  impulse  to  pass  into  the  peripheral  segment  which 
has  remained  intact  and  to  supply  afresh  the  paralysed  muscles. 

If  the  fibres  are  more  deeply  affected,  the  peripheral  segment  is  injured 
secondarily,  and  the  work  of  restoration  must  be  carried  on  over  the  entire 
extent  of  the  nerve. 

The  extreme  variations  we  find  in  the  time  necessary  for  healing  may 
thus  be  understood. 

In  almost  every  case  of  compression  calling  for  surgical  intervention, 
simple  liberation  of  the  nerve  is  usually  sufficient.  Resection  and  suture 
are  called  for  only  in  cases  where  prolonged  constriction  has  transformed 
the  nerve  into  a  mere  fibrous  strand  ;  in  these  cases,  the  syndrome  of 
compression  had  given  place  to  that  of  complete  interruption. 


III.— SYNDROMES   OF   IRRITATION 

Irritation  of  a  nerve  trunk  may  show  itself  by  extremely  varied  and 
diversely  associated  symptoms. 

We  will  describe  schematically  : 

i.  Serious  nerve  irritation  ; 

2.  Slight  nerve  irritation  ; 

3.  Irritation  of  a  simple  neuralgic  form  ; 

4.  A  special  neuralgic  syndrome  accompanied  by  violent  pains  and  paroxysms  ; 

the  causalgia  of  Weir  Mitchell. 

The  phenomena  of  nerve  irritation  or  neuralgia  in  a  mixed  nerve  may  be 
associated  with  paralysis,  though  they  may  also  exist  without  total  paralysis. 
It  may  even  be  stated  that  paralysis  is  exceptional  in  slight  neuritic  forms, 
and  in  neuralgic  forms. 

On  the  other  hand,  disturbances  of  irritation  also  show  themselves  in 
the  sensory  nerves  or  in  the  purely  sensory  branches  of  the  mixed  nerves. 


CLINICAL   TYPES  67 


I.— SYNDROME   OF   SERIOUS   NERVE    IRRITATION 

This  syndrome  is  found  only  in  lesions  of  the  mixed  nerves  which  alone 
possess  numerous  vaso-motor  and  trophic  fibres  whose  irritation  produces 
neuritic  disturbances. 

It  is  almost  always  accompanied  by  paralysis  ;  this  paralysis,  however,  is 
frequently  less  complete  than  in  the  preceding  forms,  for  the  nerve  fibres 
are  irritated,  not  destroyed.  For  instance,  there  persists  a  suggestion  of 
voluntary  movements  or  else  a  certain  degree  of  electrical  excitability. 
The  RD  is  frequently  partial. 

Muscular  atrophy  isextremely  variable.  Whilst,  for  the  most  part,  it  is  less 
marked  by  reason  of  the  relative  preservation  of  the  nerve  fibres,  in  other 
cases  we  find  extremely  rapid  muscular  dissolution. 

Muscular  tone  is  usually  preserved,  sometimes  even  intensified  by 
fibrous  infiltration  of  the  muscles. 

The  idio-muscular  reflexes  are  always  intensified,  although  the  fibrous 
transformation  of  the  muscles  may  frequently  mask  them. 

Trophic  and  painful  sensory  disturbances  are  the  essential  characteristics 
of  neuritic  types. 

Whereas,  however,  motor  disturbances  occur  immediately,  pains  and 
trophic  disturbances  are  secondary. 

After  a  few  days  the  pain  appears  and  it  gradually  becomes  more 
pronounced  for  two  or  three  weeks,  to  continue  for  months  and  then 
slowly  disappear. 

It  is  also  after  a  few  weeks  that  trophic  disturbances  appear,  persistence 
of  which  often  brings  about  definite  lesions. 


A. — Sensory  Disturbances 

Pains. — The  main  symptom  is  pain. 

Spontaneous  pains  comparable  to  sensations  of  burning,  pricking) 
muscular  rending. 

Pains  intensified  by  movement  and  muscular  contraction,  by  heat  and 
more  especially  by  cold,  by  cutaneous  friction  or  by  contact  of  the  bed- 
clothes. 

Pains  occasioned  mainly  by  pressure  on  nerve  trunks  and  muscular 
bellies  ;  these  pains  are  felt  at  the  compressed  point;  they  also  extend  over 
the  whole  limb.  Generally  they  are  more  acute  on  pressure  of  the 
muscles  than  of  the  nerve  trunks. 

Cutaneous  hyperesthesia. — The  skin  also  is  painful.  In  certain  cases, 
it  is  true,  we  may  note  the  presence  of  cutaneous  anesthesia,  which,  however, 
is  found    along  with   the  pain   on   pressure    of   the    deeper  tissue.      More 


68  NERVE   WOUNDS 

frequently,  however,  there  is  painful  hyperesthesia,  which  usually  coexists 
with  a  tactile  and  thermal  hypo-aesthesia. 

Indeed,  touch,  friction,  cold  and  heat  are  but  vaguely  perceived  ;  even 
pricking  is  ill  defined  ;  but  all  these  cutaneous  stimuli  produce  one  and 
the  same  painful  sensation,  imperfectly  localised  and  differentiated,  diffuse, 
radiated,  continuing  several  seconds  and  altogether  characteristic. 


B. — Trophic  Disturbances 

Trophic  disturbances  belong  strictly  to  the  syndrome  of  nerve  irritation. 

In  these  cases  we  note  the  presence  of  cedema,  cyanosis  and  hyper- 
trichosis, already  found  in  nerve  interruption. 

More  especially  do  we  find  the  whole  series  of  severe  trophic  dis- 
turbances— 

Extreme  dryness  of  the  skin,  its  fibrous  infiltration  and  its  desquamation 
in  broad  scales,  or,  on  the  other  hand,  the  appearance  of  profuse  fetid  sweats, 
or  again  the  condition  known  as  glossy  skin. 

Nails  curved,  furrowed,  split,  cracked,  claw-like. 

Conical  atrophy  of  the  digital  extremities. 

Fibrous  infiltration  and  contraction  of  the  muscular  bellies  ;  contraction 
of  the  tendons  and  aponeuroses,  which  lead  to  the  formation  of  irreducible 
griffes. 

Immobilisation  of  the  tendons  by  fibrous  invasion  of  the  synovial  sheaths. 

Fibrous  ankyloses  of  digital  or  carpal  joints  and  of  deformed  joints 
reminiscent  of  rheumatoid  arthritis. 

A  more  rapid  and  pronounced  bony  decalcification  than  in  any  other 

type. 

***** 

Pronounced  neuritic  types  are  therefore  essentially  serious,  mainly  by 
reason  of  their  trophic  disturbances. 

Indeed,  whilst  the  paralyses  that  accompany  them  are  always  destined 
to  heal  spontaneously  or  by  liberation  of  the  nerve,  the  pains  that  characterise 
them,  however  acute  they  may  be,  must  inevitably  diminish  and  disappear  ; 
on  the  other  hand,  the  fibrous  and  mucular  contractions,  the  tendon 
immobilisations,  the  griffes,  the  articular  scleroses,  too  often  constitute 
refractory  lesions  which  necessitate  months  or  even  years  of  painful 
mobilisation  and  of  massage,  and  sometimes  remain  altogether  irreducible. 

Most  of  these  severe  neuritic  types  heal  spontaneously,  with  the 
exception  of  the  fibrous  sequelae  of  the  healing  process. 

Spontaneous  regression  is  indicated  by  the  mitigation  of  pain  and  by 
the  appearance  of  formication. 

During  the  entire  period  of  irritation,  the  nerve  is  painful,  though 
there  is  no  formication  when  pressure  is  applied.  As  soon  as  neuritis 
calms  down,  we  note  the  appearance  of  formication  at  the  level  of  the 


CLINICAL   TYPES  69 

lesion  ;  then,  week  by  week,  it  is  seen  to  descend  along  the  tract  of  the 
nerve  which,  with  the  neighbouring  muscles,  ceases  to  be  painful  ;  formi- 
cation then  gradually  replaces  in  the  nerve  the  neuritic  pain,  driving  it 
forward,  as  it  were.  Speaking  generally,  the  slowness  of  the  regeneration 
in  neuritic  types  is  discouraging. 

In  obstinate  cases,  liberation  of  the  nerve  seems  to  give  variable  results  ; 
sometimes  it  brings  about  a  great  and  rapid  improvement  ;  frequently  it  is 
ineffective.  Probably  the  inconstant  nature  of  the  results  is  due  to  the 
character  of  the  lesion  ;  irritation  may  be  external  to  the  nerve,  or,  on  the 
other  hand,  may  take  place  within  it. 

In  certain  particularly  intense  forms,  where  serious  and  definite  trophic 
disturbances  are  to  be  feared,  it  is  right  to  practise  resection  of  the  lesion 
and  suture  of  the  nerve.  By  this  means,  the  pains  are  immediately  dis- 
pelled, the  evolution  of  trophic  disturbances  is  suppressed  and  it  is  possible 
to  practise  massage,  mobilisation  and  electrical  treatment,  all  of  which  had 
been  impossible  before  by  reason  of  the  intensity  of  the  pains. 


II.— ATTENUATED   NEURITIC  TYPE 

We  have  described  the  grave  forms  of  nerve  irritation,  but  we  must 
remember  that  its  manifestations  may  be  far  more  widely  disseminated. 

A  little  pain  on  pressure  of  the  muscular  bellies,  a  slight  fibrous  infil- 
tration of  the  muscles,  a  few  aponeurotic  or  tendon  contractions,  slight 
cutaneous  sclerosis  with  adhesion  of  the  integuments  enable  us  to  conclude 
that  there  is  irritation  of  the  nerve  and  therefore  that  it  is  incompletely 
interrupted. 

Frequently  slight  neuritic  disturbances  may  be  dissociated.  For 
instance,  we  may  find  pain  on  pressure  of  the  muscles,  with  fibrous  con- 
traction but  without  pronounced  cutaneous  trophic  disturbances  ;  this  is 
the  origin  of  some  cases  of  pes  equinus,  from  slight  lesion  of  the  sciatic. 
Muscular  atrophy  may  be  absent,  we  have  even  seen  cases  where  slight 
irritation  of  the  sciatic  nerve  was  shown  by  actual  hypertrophy  of  the 
muscles  of  the  calf,  accompanied  by  slight  contraction  and  fibrous  infiltra- 
tion of  the  muscles,  more  bulky  and  resisting  than  on  the  healthy  side. 
Moreover  we  shall  see  later  what  relations  can  be  established  between 
these  disturbances  and  contractions  from  neuritis. 

In  these  cases  of  neuritis  affecting  the  muscular  system  we  occasionally 
find  neither  hyperesthesia  nor  even  cutaneous  hypoaesthesia  ;  whilst,  on 
the  other  hand,  the  muscles  are  painful  when  pressed.  The  pain  is  deep, 
not  on  the  surface. 

In  other  cases  aponeurotic  contractions  prevail,  resulting  in  the  forma- 
tion of  fibrous  grijfcs ;  sometimes  nerve  irritation  is  rather  ill-defined  and 
aponeurotic  sclerosis  so  tardy  that  the  nerve  lesion  may  pass  unnoticed. 


7o  NERVE   WOUNDS 

For  instance,  we  have  seen  cases  of  contraction  of  the  palmar  fascia, 
reminding  one  of  Dupuytren's  contracture,  occurring  slowly  after  a 
wound  in  the  arm  or  the  fore-arm  and  apparently  inexplicable ;  the  most 
minute  investigation  has  been  needed  to  discover,  not  only  a  certain 
degree  of  pain  on  pressing  the  nerve,  but  even  slight  formication  along  its 
course  and  hypo-aesthesia  of  its  cutaneous  area,  thus  proving  slight  irritation 
of  the  ulnar. 

Sometimes  again  cutaneous  trophic  disturbances  preponderate.  In 
certain  slight  neurites  of  the  musculo-spiral,  for  instance,  attention  is 
first  attracted  by  the  fibrous  infiltration  of  the  skin  on  the  dorsal  surface  of 
the  fingers,  its  adhesion  to  the  first  joints  and  the  limitation  resulting 
therefrom  in  flexion  of  the  fingers. 

Still,  speaking  generally,  the  exclusively  cutaneous  manifestation  of 
trophic  disturbances  is  more  apt  to  accompany  the  neuralgic  type  which 
we  will  now  investigate. 


III.— SIMPLE  NEURALGIC  TYPE 

Following  on  slight  bruises  of  the  nerve  trunks,  we  often  meet  with 
more  or  less  pronounced  neuralgic  syndromes. 

No  trophic  disturbances  occur,  at  most  a  few  signs  of  cutaneous  irrita- 
tion. There  is  no  paralysis,  but  only  a  certain  degree  of  weakness  and 
muscular  atrophy,  without  appreciable  modification  of  the  electrical 
reactions. 

Instead  of  anaesthesia,  there  is  slight  hyper-aesthesia  to  pin-prick  in 
the  area  of  distribution  of  the  nerve. 

The  patient  complains  solely  of  more  or  less  acute  pains  radiating 
along  the  course  of  the  nerve,  provoked  mainly  by  the  movements  involving 
the  lengthening  of  the  limb,  such  as  the  extension  at  elbow,  neck  and 
knee  in  the  case  of  the  median  and  the  sciatic,  which  are  most  frequently 
involved. 

The  muscular  bellies  are  somewhat  sensitive  to  pressure.  The  nerve 
trunks,  however,  are  more  so  ;  and  this  pain  is  manifested  above  all  at  the 
points  of  election.  On  the  sciatic  are  found  all  the  Valleix  points  and 
Lasegne's  sign  ;  indeed,  we  are  dealing  with  real  injuries  to  the  sciatic. 

These  traumatic  neuralgias  are  often  rather  persistent,  they  may  con- 
continue  for  several  months  and  then  disappear  spontaneously. 

Naturally  their  intensity  is  very  variable,  and  every  type  may  be  found. 
They  are  syndromes  of  slight  irritation,  of  a  well-marked  sensory  type. 

They  are  specially  to  be  distinguished  from  the  violent  neuralgic 
syndromes  of  a  particular  character,  for  which  must  be  reserved  the  name 
of  "  causalgia." 


CLINICAL   TYPES  71 


IV.— INTENSE   NEURALGIC  TYPE— CAUSALGIA 

In  1864,  after  the  War  of  Secession,  S.  Weir  Mitchell  descrihed  under 
the  name  of  causalgia  a  particular  neuralgic  syndrome,  characterised  hy  its 
intensity,  its  long  duration,  its  special  pains  and  its  habitual  resistance  to 
every  therapeutic  agency. 

All  the  nerves  may  be  attacked  by  causalgia,  but  it  is  particularly  the 
median  and  the  sciatic  that  produce  this  syndrome,  doubtless  by  reason 
of  the  number,  importance,  and  perhaps  fragility  or  special  .nature,  of  their 
sensory  or  vaso-motor  fibres. 

Very  seldom  does  causalgia  appear  immediately  after  the  wound  ; 
almost  always  the.  pains  supervene  only  after  four  or  five  days;  they 
take  three  or  four  weeks  to  reach  their  maximum,  and  then  continue  for 
months,  finally  calming  down  very  slowly. 

Causalgia  is  essentially  characterised  by  violent  pains,  compared  by 
patients  to  a  sensation  of  mingled  smarting  and  burning  (kq,v<tiq,  burning), 
or  even,  says  Weir  Mitchell,  "to  a  red-hot  file  rasping  the  skin.  .  .  . 
Its  intensity  varies  from  the  most  trivial  burning  to  a  state  of  torture  that 
can  hardly  be  credited.* 

As  a  rule,  it  is  localised  at  the  termination  of  the  nerve,  at  the  palm  of 
the  hand  in  the  case  of  the  median,  at  the  sole  of  the  foot  in  the  case  of 
the  sciatic  ;  but  it  radiates  simultaneously  over  the  entire  area  of  distribu- 
tion of  the  nerve  and  even  well  above  the  lesion. 

The  pains  are  so  greatly  aggravated  by  movement,  walking  or  the 
slightest  shock,  that  certain  patients  resign  themselves  to  almost  complete 
immobility. 

A  slight  touch  on  the  skin,  a  pin-prick,  heat,  cold  especially,  and  all 
cutaneous  excitations,  induce  painful  paroxysms  which  often  continue  for 
several  minutes. 

Accordingly  these  patients  show  the  greatest  anxiety  when  we  want  to 
examine  the  hand.  And  yet,  whilst  a  gentle  touch  is  atrociously  painful, 
firm  pressure  of  the  integuments  can  scarcely  be  felt.  By  warning  the 
patient  beforehand,  we  may  succeed  in  openly  grasping  his  hand  and 
examining  it  without  causing  him  too  much  suffering.  The  pain  is  tar 
more  superficial  than  deep.  "  If  it  lasted  long,  it  was  referred  finally  to 
the  skin  alone,"  writes  Weir  Mitchell. 

An  even  more  curious  fact, — keen  emotions  and  sensations  induce 
violent  exacerbations  of  pain  ;  a  child  falling,  an  unexpected  letter  arriving, 
a  carriage  appearing  at  the  bend   of  a  street,  a   door  creaking,  a  sudden 

*  S.  Weir  Mitchell,  Morehouse  and  Keen,  "  Gunshot  Wounds  and  other  Injuries  of  Nerves." 
Philadelphia,  1864,  p.  ioi,etc. 

Des  lesions  des  nerfs  et  de  leurs  consequences.  Traduction  Dastre,  preface  <le  Vulpian,  Paris, 
1874,  p.  233,  etc. 


72  NERVE   WOUNDS 

strong  light,  a  glance  down  a  staircase  or  through  a  window,  are  all  so 
many  causes  calculated  to  provoke  a  painful  paroxysm. 

We  now  understand  why  those  who  suffer  from  violent  causalgia  have 
so  distinctive  an  appearance  :  they  look  anxious,  they  are  taciturn  and 
irritable,  they  will  not  leave  the  house  or  speak  or  play,  they  lose  both 
sleep  and  appetite.  They  walk  daintily  as  though  to  avoid  all  shock  ;  in 
some  cases  the  hand  is  held  behind  the  back,  in  others  it  is  held  in  front, 
the  healthy  hand  acting  as  a  shield  to  protect  the  other  from  contact  of 
every  kind. 

The  dryness  of  the  skin  causes  particularly  painful  sensations.  To 
calm  their  sufferings  and  at  the  same  time  avoid  contact  with  the  air,  the 
patients  wrap  the  hand  in  compresses  or  padded  gloves ;  moisture  more 
than  anything  else  gives  them  appreciable  relief;  they  are  often  seen  to 
surround  the  hand  with  a  wet  cloth  constantly  renewed. 

"  Most  of  the  bad  cases,"  says  Weir  Mitchell,  "  keep  the  hand  con- 
stantly wet,  finding  relief  in  the  moisture  rather  than  in  the  coolness  of 
the  application.  Two  of  these  sufferers  carried  a  bottle  of  water  and  a 
sponge,  and  never  permitted  the  part  to  become  dry  for  a  moment.  .  .  . 
One  of  these  men  went  so  far  as  to  wet  the  sound  hand  when  he  was 
obliged  to  touch  the  other  "  ;  others  "  found  some  ease  from  pouring  water 
into  their  boots." 

Along  with  the  pains  which  constitute  the  main  symptom  of  causalgia, 
other  less  important  disturbances  must  be  mentioned.  If  there  is  no 
paralysis  but  at  most  a  slight  muscular  weakening  and  atrophy,  the  vaso- 
motor and  trophic  disturbances  are  often  a  little  more  pronounced. 

The  skin,  usually  macerated  by  the  moist  state  kept  up,  is  smooth, 
warm  and  red,  the  glossy  skin  type  described  by  Weir  Mitchell.  It  is  some- 
times more  dry  than  on  the  healthy  side  ;  though  more  frequently  causalgia 
would  seem  to  be  accompanied  by  profuse  sweats.  The  fingers  are  thin 
and  slender  ;  flexion  of  the  last  phalanx  is  often  limited.  The  slightly 
striated  nails,  sometimes  a  little  bent,  are  almost  always  of  a  dull  yellow 
colour  resembling  ivory.  They  grow  more  quickly  than  in  their  normal 
state,  and  their  rapid  growth  raises  at  the  extremity  of  the  finger  a  small 
cutaneous  swelling,  constant  in  all  nerve  irritations  and  particularly  painful 
in  causalgia. 

The  skin  shows  extreme  hyper-assthesia,  entirely  superficial,  almost 
always  passing  beyond  the  cutaneous  region  of  the  nerve. 

Strange  to  say,  the  vaso-motor  disturbances,  redness  of  the  skin,  dryness 
or  exaggerated  sweating,  like  hyper-aesthesia,  often  extend  far  beyond  the 
cutaneous  region  of  the  nerve  affected. 

Those  authors  base  their  conclusions  on  this  fact  who  tend  to  regard 
causalgia  as  the  syndrome  of  irritation  of  the  vascular  nerves,  supplied  by 
the  median  or  the  sciatic  to  the  arteries  which  they  accompany,  or  even  as 
a  sympathetic  syndrome  indicating  lesion  of  the  pcri-arterial  plexuses. 


CLINICAL   TYPES  73 

In  all  cases,  the  refractory  nature  of  these  disturbances  is  disheartening. 
No  treatment  relieves  them  ;  liberation  of  the  nerve  remains  almost  always 
ineffectual  ;  sedative  electrical  treatment  obtains  ease  only  for  a  few  hours. 

In  these  conditions,  some  authors  considered  the  question  of  section  of 
the  nerve  or  the  injection  of  alcohol  above  the  lesion,  but  even  these  heroic 
measures  may  be  ineffectual  ;  after  resting  for  a  few  days,  the  patient 
again  begins  to  suffer.  Regeneration  of  the  cut  fibres  seems  to  take  place 
with  extraordinary  rapidity  ;  cutaneous  hyper-aesthesia  soon  reappears  and 
the  muscles  themselves  rapidly  regain  all  their  excitability. 

Further  on,  we  shall  study  the  various  treatments  proposed  ;  both 
failures  and  successes  attend  almost  all  therapeutic  measures.  The  present 
therapeutic  uncertainty  is  largely  owing  to  our  ignorance  of  the  true 
mechanism  of  causalgia. 

Not  without  a  certain  repugnance  can  we  assent  to  cutting  or  alcoholising 
a  nerve  trunk  which  is  not  paralysed,  and  the  regeneration  of  which,  after 
intervention,  is  never  certain. 

Radiotherapy  in  certain  cases  has  given  remarkably  soothing  effects. 

The  paroxysmal  symptoms  of  causalgia,  the  pains  of  an  emotional 
type,  the  vaso-motor  disturbances  and  the  radiation  of  the  symptoms 
beyond  the  region  of  the  nerve  clearly  indicate  a  sympathetic  syndrome. 
(  Leriche,  Meige  and  Mme  Benisty.) 

Denudation  of  the  brachial  artery  and  section  of  the  sympathetic 
plexus  surrounding  it,  recommended  by  Leriche,  have  given  good  results 
in  obstinate  cases. 


V.— HYPERTONIA  AND   CONTRACTION   FROM   NERVE 
IRRITATION 

We  have  already  mentioned  the  cases  in  which  slight  nerve  irritation 
produced  simple  contraction  and  fibrous  infiltration  of  the  muscles,  without 
paralysis  or  strongly  marked  muscular  atrophy.  These  are  indisputable 
and  well-known  facts. 

But  it  would  also  seem  that  irritation  of  a  nerve  trunk  might  produce 
states  of  muscular  hypertonia,  veritable  nerve  contractions,  immobilising 
the  muscles  in  a  frequently  paradoxical  posture. 

As  a  matter  of  fact,  these  contractions  from  neuritis  are  often  of  a 
more  complex  nature  ;  we  shall  study  them  later  on. 


IV.— SYNDROME   OF   REGENERATION 

The  syndrome  of  regeneration  is  seen  in  its  purest  form  after 
nerve  sections  and  nerve  sutures;  it  exists  in  the  compressions,  crushings 
or  tearings  which  are   accompanied  by  complete  or  partial  interruption  of 


74  NERVE    WOUNDS 

a  nerve  trunk  ;  it  is  also  shown  in  cases  of  severe  nerve  irritation  where 
the  affected  or  irritated  nerve  fibres  seem  to  have  been  gradually  replaced 
by  young  and  healthy  ones. 

Thus  it  indicates  the  slow  progression  of  the  regenerating  axis-cylinders, 
coming  from  the  central  end,  into  the  empty  sheaths  of  the  degenerated 
peripheral  segment. 

No  interrupted  or  even  severely  injured  nerve  fibre  can  resume  its 
functions  except  by  this  budding  of  the  axis-cylinders  from  the  central 
end. 

The  regeneration  of  a  nerve  is  essentially  a  long  and  gradual 
process. 

Again  we  must  repeat  that  immediate  or  even  rapid  restoration  of  an 
interrupted  and  sutured  nerve,  however  short  the  interruption,  is  theoretically 
and  practically  impossible.  No  fact  of  this  kind  has  ever  been  ascertained 
by  a  neurologist  ;  all  reported  observations  are  errors  of  interpretation 
caused  by  compensatory  movements  or  by  phenomena  of  collateral  sensi- 
bility. 

The  syndrome  of  regeneration,  then,  consists  of  the  progressive 
reappearance  of  the  functions  of  a  nerve  :  motor,  sensory,  trophic  func- 
tions and  electrical  reactions. 

The  beginning  of  restoration  after  a  suture  or  a  traumatic  interruption 
of  the  nerve  is  never  immediate ;  the  first  signs  of  regeneration  scarcely 
ever  appear  before  the  fourth  or  even  the  sixth  week. 

Any  interruption  of  nerve  fibres  produces  two  kinds  of  phenomena. 
On  the  one  hand,  it  is  followed  by  the  degeneration  of  the  whole  peripheral 
segment  :  Wallerian  degeneration.  On  the  other  hand,  it  causes  a  series 
of  profound  disturbances  in  the  central  segment  ;  this  is  first  an  ascending 
degeneration  of  the  nerve  fibre  above  the  lesion,  a  retrograde  degeneration, 
which  is  always  limited,  and  does  not  extend  more  than  a  few  millimetres, 
and  afterwards  the  reaction  a  distance  on  the  original  cell,  shown  under  the 
microscope  as  the  phenomenon  of  cellular  chromatolysis.  Only  after  this 
brief  disturbance  in  the  nerve  does  proliferation  of  the  axis-cylinders  of  the 
central  end  and  their  advance  towards  the  peripheral  segment  begin,  and 
the  first  signs  of  regeneration  become  manifest. 

Return  of  the  functions  of  the  nerve  corresponds  with  progression  of 
the  axis-cylinders  in  the  degenerated  nerve  ;  consequently  it  follows  a 
centrifugal  course,  i.e.  restoration  is  first  shown  at  the  level  of  the  muscles 
and  integuments  nearest  the  lesion,  gradually  and  slowly  extending  to  the 
more  distant  muscles  and  integuments. 

This  progress- is  not  absolutely  regular  ;  it  often  takes  place  in  jumps, 
during  periods  of  a  few  days  when  the  regenerating  activity  manifests 
itself,  followed  by  periods  of  rest. 

In  all  cases  regeneration  is  shown  in  the  nerve  trunk,  in  the  muscles 
and  in  the  integuments. 


CLINICAL   TYPES  75 

I.— SIGNS   OF   REGENERATION    OF   THE   NERVE 

In  the  nerve  two  signs  of  regeneration  may  be  observed  : 

The  appearance  of  formication  called  forth  by  pressure  ; 

The  return  of  electrical  conductivity. 

The  former  comes  about  at  a  very  early  stage  and  is  most  important  ; 
the  latter  is  tardy,  almost  always  following  on  the  return  of  voluntary 
conductivity  ;   it  is  consequently  devoid  of  interest. 

The  all-important  sign  is  formication.  We  find  that  sudden  pressure, 
or  percussion  of  the  nerve  trunk,  below  the  lesion,  calls  forth  a  sensation 
of  formication  in  the  cutaneous  region  of  the  nerve. 

It  appears  about  the  fourth  or  sixth  week.  Then  it  gradually  becomes 
more  pronounced,  and  it  is  possible  to  follow,  week  after  week,  in  the 
course  of  the  nerve,  the  progress  of  this  provoked  formication,  pari  passu 
with  the  advance  of  the  axis-cylinders.  It  extends  towards  the  periphery, 
reaches  the  parts  where  the  nerve  divides,  and  ends  after  a  few  months  by 
reaching  the  cutaneous  region  itself. 

The  more  it  extends  and  shows  itself  towards  the  periphery  of  the 
nerve,  the  less  marked  it  becomes,  finally  disappearing  at  the  level  of  the 
portions  of  the  nerve  which  are  nearest  the  lesion.  Consequently,  there  is 
in  the  course  of  the  nerve  a  wide  zone  of  formication  which  can  be 
brought  on,  spreads  centrifugally,  corresponds  to  the  zone  of  growth  of  the 
young  axis-cylinders  and  at  last  completely  disappears  when  the  nerve  fibres 
have  regained  their  fully  formed  state. 

Let  us  follow,  for  instance,  the  progress  of  formication  on  a  sciatic 
nerve  sutured  in  the  middle  of  the  thigh  :  about  the  fourth  week  formi- 
cation appears  at  the  level  of  the  suture ;  about  the  eighth  week  it  is 
ascertained  to  be  a  few  centimetres  below  ;  after  three  months  it  reaches 
the  popliteal  space  ;  at  the  fourth  month  we  find  it  on  the  internal  and 
external  popliteal  nerves  at  the  upper  third  of  the  leg,  but  at  the  same  time 
it  has  disappeared  at  the  level  of  the  lesion  ;  at  the  fifth  month  the  nerve 
formicates  on  pressure  from  the.  popliteal  space  to  the  level  of  the  malleoli  ; 
finally,  in  the  sixth  month,  it  has  reached  the  foot,  but  has  disappeared  as 
far  as  the  upper  third  of  the  leg. 

Formication  is  the  best  and  almost  the  only  sign  of  regeneration  of  the 
nerve  ;  for  not  only  does  it  enable  us  to  follow  the  progress  of  regeneration, 
but  through  its  intensity,  rapidity  of  migration  and  the  region  in  which  it 
appears,  it  even  supplies  exact  information  regarding  the  quality,  extent  or 
limitation  of  regeneration. 

If  the  axis-cylinders  stray  and  lose  themselves  in  the  tissues  next  to  the 
lesion,  formication  reveals  them  ;  thus,  in  an  interruption  of  the  musculo- 
spinal, Andre-Thomas  was  able  to  demonstrate  the  presence  of  stray  axis- 
cylinders  in  the  muscles  of  the  forearm. 

Any  nerve  that  formicates  below  the  lesion  is  a  nerve  in  course  ol 
regeneration,  either  partially  or  wholly  ;  absence  of  formication  over  the 


76  NERVE   WOUNDS 

entire  extent  of  a  degenerated  nerve  trunk  is  an  almost  certain  sign  of 
absence  of  regeneration. 

II.— SIGNS   OF   MUSCULAR   REGENERATION 

These  are — 

The  appearance  of  muscular  tone. 
The  return  of  muscular  sensibility. 
The  diminution  of  atrophy. 
The  modification  of  electrical  reactions. 
The  return  of  voluntary  movement. 

Naturally  all  these  signs  take  place  muscle  by  muscle,  one  after  another, 
in  the  order  in  which  regeneration  of  the  axis-cylinders  reaches  them  ; 
accordingly  we  find  different  results  in  neighbouring  muscles  ;  it  might 
almost  be  said  that  we  find  in  the  same  muscle  different  results  according 
to  the  fasciculi  examined. 

The  return  of  muscular  tone  seems  to  be  the  first  sign  of  regeneration. 
It  shows  itself  in  the  firmer  consistence  of  the  muscles  on  palpation,  and 
especially  in  progressive  modification  of  the  paralytic  posture  of  the  limb, 
which  loses  any  tendency  to  be  excessive  and  approaches  a  state  of 
normal  rest. 

The  diminution  of  muscular  atrophy  is  far  more  tardy  ;  still,  it  may 
considerably  precede  the  return  of  voluntary  movements.  Atrophy,  how- 
ever, does  not  completely  disappear,  except  by  massage,  gymnastics  and 
repeated  electrical  stimulation,  until  many  months  after  the  return  of  all  the 
motor  functions. 

The  appearance  of  muscular  sensibility  is  perhaps  the  earliest  sign  after 
the  return  of  tone.  Nevertheless  it  follows  regeneration  so  far  that  we 
may  regard  the  coexistence  of  tone  and  muscular  analgesia  as  a  sure  sign 
of  regeneration  after  interruption  of  the  nerve. 

Electrical  sensibility  is  perhaps  the  first  to  reappear ;  then  comes 
sensibility  to  pressure. 

The  return  of  voluntary  movement  is  the  latest  manifestation  of 
regeneration. 

At  first  it  shows  itself  by  a  slight  hardening  of  the  muscle,  which 
accompanies  the  efforts  of  the  patient,  and  particularly  the  energetic 
contraction  of  the  antagonistic  muscles ;  no  movement,  however,  is 
apparent. 

Then  there  appear  faint  voluntary  movements,  necessitating  considerable 
effort  on  the  part  of  the  patient  and  bringing  into  play  the  violent  synergic 
contraction  of  all  the  muscles  of  the  limb. 

Finally  the  movements  become  definite  but  they  long  remain  weak, 
awkward,  clumsy  and  quickly  exhausted,  inducing  rapid  fatigue  accompanied 
by  slight  trembling. 

Only  by  daily  exercise  will  patients  regain  the  full  range  and  dexterity 
of  their  movements. 


CLINICAL   TYPES  77 


III.— ELECTRICAL   REACTIONS 

During  the  entire  regeneration,  the  electrical  reactions  arc  gradually 
modified. 

These  modifications  seem  to  take  place  in  somewhat  variable  order, 
according  to  the  case. 

Moreover,  they  are  difficult  to  interpret,  for  certain  of  these  electrical 
modifications  seem  clearly  anterior  to  the  arrival  of  the  axis-cylinders  in  the 
paralysed  muscles.  Some  patients,  for  instance,  undergoing  electrical  treat- 
ment immediately  after  a  nerve  suture,  show  electrical  signs  of  ameliora- 
tion long  before  nerve  regeneration  can  have  reached  the  muscles  ;  some, 
previously  untreated,  show  almost  complete  electrical  inexcitability  and 
rapidly  regain  their  galvanic  excitability  ;  in  others  we  find  that  their 
galvanic  hypo-excitability  diminishes. 

Probably  massage  and  electrical  treatment  have  simply  improved  the 
contractility  of  the  paralysed  muscles.  These  latter,  from  disuse  and  lack 
of  attention,  showed  the  early  stages  of  fibrous  transformation  with  the 
syndrome  of  muscular  hypo-excitability,  which  the  treatment  causes  to  dis- 
appear gradually. 

These,  however,  are  modifications  in  quantity,  not  in  quality  ;  the  RD, 
with  all  its  characteristics,  persists  ;  it  begins  to  be  qualitatively  modified 
only  on  the  arrival  of  the  axis-cylinders  and  after  the  reappearance  of 
tone. 

First  of  all,  galvanic  hypo-excitability  is  seen  to  diminish  at  the  motor 
point  ;  the  closing  contraction  at  the  negative  pole  becomes  stronger  and 
finally  equals  the  contraction  at  the  positive.  There  is  polar  equality  at  the 
motor  point  ;  then  the  formula  again  becomes  normal,  the  negative 
contraction  stronger  than  the  positive. 

At  the  same  time,  longitudinal  reaction  becomes  less  clear  ;  the  muscle 
gradually  loses  its  longitudinal  hyper-excitability,  its  excitation  at  the  motor 
point  becomes  predominant. 

The  contraction,  however,  remains  slow  for  a  very  long  time  ;  still,  it 
gradually  accelerates,  but  whilst  becoming  shorter  and  shorter  at  the  motor 
point,  it  remains  slow  to  longitudinal  excitation  for  a  longer  time. 

The  slowness  of  the  contraction  generally  disappears  completely  only 
after  the  return  of  the  first  voluntary  movements. 

It  is  a  generally  recognised  fact  that  faradic  excitability  reappears  only 
after  the  voluntary  movements. 

This  rule  is  true  if  the  usual  thick  wire  coils  are  utilised. 

It  is  not  true,  as  we  have  seen,  if  the  muscle  is  examined  with  thinner 
wire  coils  of  greater  resistance  and  electro-motive  force. 

Thus,  with  the  thin  wire  coils  of  the  ordinary  apparatus,  we  find,  as 
P.  Marie,  Meige,  and  Mme  Benisty  have  shown,  that  there  exist  muscular 
contractions  which  long  precede  the  appearance  of  voluntary  movements. 


78 


NERVE   WOUNDS 


IV.— SENSORY   SIGNS   OF   REGENERATION 

Regeneration  of  the  sensory  functions  takes  place,  like  that  of  the 
muscular  functions,  by  centrifugal  extension. 

1.  Patients  often  complain  of  spontaneous  sensations,  more  disagreeable 
than  painful,  which  assume  the  form  of  shooting  pains  and  especially  of 
formication  felt  in  the  cutaneous  region  of  the  nerve. 

These  sensations  often  occur  rather  early,  and  generally  it  is  not  possible 
to  regard  them  as  a  sign  of  cutaneous  restoration. 

Indeed,  we  are  now  considering  excitation  of  the  nerve  itself,  in  process 
of  regeneration  ;  this  is  nothing  else  than  the  sign  of  spontaneous 
formication.  Movements,  muscular  contractions,  cutaneous  pressure  or 
slight  touch,  when  transferred  to  the  nerve  trunk,  induce  formication  of 
the  axis-cylinders  in  process  of  regeneration. 

At  a  later  period  there  are  observed  sensations  of  cutaneous  itching, 
soothed  by  scratching  or  friction  ;  these  seem  to  be  connected  with  the 
paresthesia  we  shall  study  shortly. 

2.  Narrowing  and  disappearance  of  the  zones  of  anaesthesia. — The 
anaesthetised  regions  gradually  shrink ;  but  this  progressive  diminution 
mostly  takes  place  from  above  downwards,  following  the  growth  of  the 
axis-cylinders. 


25th  day  '  55th  day  77th  day  103rd  day 

Fig.  23. — An  instance  of  sensory  restoration  (after  suture  of  the  sciatic).  There  may 
be  distinguished  three  schematic  zones  :  a  zone  of  total  anaesthesia  ;  a  zone  of  hypo- 
sesthesia  where  pricking  is  felt  as  touch  ;  a  zone  of  hypo-xsthesia  with  paresthesia 
of  regeneration  (cutaneous  formication). 

The  return  of  the  deep  sensibilities  is  always  earlier  than  that  of  the 
superficial  ones ;  the  slightest  pressure  of  the  skin  is  felt,  whereas  pricking, 
heat  and  cold  are  scarcely  perceived. 

As  a  rule,  thermal  anaesthesia  is  a  little  more  protracted  than  tactile 
painful  sensibility  and  is  always  more  widespread.  In  certain  cases  and  at 
certain  stages  of  regeneration,  this  results  in  actual  sensory  dissociations. 

Moreover,  as  the  different  sensibilities  are  restored,  they  gain  both  in 


CLINICAL   TYPES 


79 


extent  and  in  precision  ;  the  gross  sensations  of  touch,  pain,  heat  and  cold 
are  first  perceived  ;  then  slowly  these  sensations  become  definite  and  allow 
of  the  appreciation  of  the  qualities  of  contact,  the  characteristics  of  pain, 
the  shades  of  temperature  and  the  exact  localisation  of  the  sensations.  It 
is  this  progressive  restoration,  doubtless  corresponding  to  the  regeneration 
of  increasingly  delicate  terminal  apparatuses,  that  has  been  most  minutely 
described  by  Head,  who  differentiates  the  gross  protopathic  sensibilities 
from  the  finer,  epicritic  sensibilities. 

3.  Paresthesia. — This  name  describes  very  special  cutaneous  sensations 
which  are  always  found  during  nerve  regenerations. 

Generally  these  are  sensations  of  formication,  rather  intense  and  at 
times  very  disagreeable,  provoked  by  the  slightest  cutaneous  excitation. 
They  are  produced  by  touch,  pricking,  heat,  cold,  and  in  particular  by  a 
slight  stroking  of  the  skin. 

They  are  often  retarded,  at  least  on  their  first  appearance  ;  i.e.y  some- 
what prolonged  excitation  is  needed  to  produce  them. 

In  general,  they  are  diffused,  radiated  over  the  entire  region  in  the 
vicinity  of  the  excitation  and  over  the  course  of  the  restored  nerve. 

Finally,  they  are  persistent  and  are  prolonged  some  seconds  after  the 
end  of  the  excitation. 

Paresthesia  ordinarily  precedes  the  appearance  of  normal  sensibility,  so 
that  no  cutaneous  excitation  is  yet  clearly  perceived,  but  all  these  excitations 
induce  this  same  sensation  of  disagreeable,  diffused,  radiated  and  persistent 
formication. 

The  period  of  paresthesia  is  prolonged.  It  gradually  diminishes  and 
its  area  becomes  restricted  as  normal  sensibility  is  restored. 

Probably  these  special  sensations  are  due  to  the  presence  in  the  dermis  of 
the  newly  formed  axis-cylinders,  which  penetrate  there  before  the  terminal 
apparatus  is  completed  ;  occasionally,  however,  they  appear  so  early  that 
they  certainly  precede  the  regeneration  of  the  axis-cylinders  ;  their  exist- 
ence is  then  a  paradoxical  phenomenon,  the  interpretation  of  which  we 
have  so  far  been  unable  to  find. 


V.— DISAPPEARANCE   OF   TROPHIC    DISTURBANCES 

We  have  seen  that  muscular  atrophy  was  both  early  in  its  appearance 
and  slow  in  its  completion. 

Cutaneous,  tendon,  synovial,  articular  and  other  trophic  disturbances 
which  accompany  neuritic  forms  are  even  more  obstinate.  Here  too,  we 
often  have  to  deal  with  well-marked  cases  of  very  advanced  fibrosis,  the 
disappearance  of  which  requires  complete  restoration  of  the  tissues.  Their 
cure  is  particularly  long  and  difficult,  sometimes  even  impossible  ;  neuritic 
types  too  often  leave  behind  fibrous  sequela?,  muscular  contractions  or  tendon 
adhesions  which  are  positively  incurable. 


8o  NERVE   WOUNDS 


V.— DISSOCIATED    SYNDROMES 

Dissociated  syndromes  correspond  to  partial  or  unequal  lesions  of  the 
nerve  trunks. 

They  are  frequently  met  with  in  wounds  of  bulky  nerves,  particularly 
of  the  sciatic,  but  a  minute  analysis  of  the  symptoms  often  enables  us  to 
recognise,  in  a  nerve  trunk  of  less  importance,  motor  or  sensory  dissocia- 
tions which  point  to  partial  lesions. 

Consequently  we  may  find  partial  lesions  of  a  nerve  manifesting  them- 
selves by  dissociated  paralysis  confined  to  part  of  the  muscles  supplied  by 
this  nerve.  Lesions  of  the  external  or  internal  part  of  the  sciatic  trunk, 
for  instance,  paralyse  the  region  of  the  external  popliteal  nerve  or  of  the 
internal  popliteal  nerve. 

But,  on  the  other  hand,  we  may  also  find  the  association  of  unequal 
lesions  in  one  and  the  same  nerve,  expressed  by  different  syndromes. 

There  may  be,  for  instance,  complete  section  of  the  external  fasciculi 
of  the  sciatic  along  with  the  hypotonia,  degeneration,  and  fixity  of  formi- 
cation which  characterise  the  syndrome  of  interruption  ;  and,  in  the  region 
of  the  internal  popliteal  nerve,  the  return  of  tone,  the  partial  RD,  pro- 
gressive formication  and  all  the  signs  of  regeneration  which  indicate  a 
slighter  lesion,  capable  of  spontaneous  restoration. 

In  another  case,  we  may  find  associated  with  the  syndrome  of  com- 
plete interruption  over  a  part  of  the  nerve  trunk  the  painful  symptoms 
and  trophic  disturbances  which  characterise  nerve  irritation  of  the  neigh- 
bouring portion  of  the  same  nerve. 

One  may  easily  imagine  all  possible  associations  and  find  them 
exemplified. 

The  study  of  these  dissociated  types  is  of  great  importance.  It  enables 
us  to  determine  the  topographic  constitution  of  a  nerve ;  it  shows 
that  the  internal  or  external,  anterior  or  posterior  fibres  correspond  to 
different  muscular  groups  or  sensory  regions  ;  it  informs  us  what,  in  a 
nerve,  is  the  position  of  the  motor,  sensory  and  trophic  or  vaso-motor 
fibres. 

Consequently  it  confirms  the  theories  put  forward  on  the  fascicular 
structure  of  nerves. 

Further,  this  fascicular  topography  of  the  nerve  trunks  seems  suffi- 
ciently definite  to  enable  us,  according  to  the  analysis  of  symptomatic 
dissociations,  to  establish  which  is  the  wounded  part  of  a  nerve  trunk. 
On  these  partially  attacked  nerves  it  will  be  possible  to  practise  partial 
operations,  to  liberate,  remove,  and  suture  only  the  affected  or  destroyed 
part  of  a  traumatised  nerve  whilst  respecting  the  healthy  fibres.  It  will 
be  known  beforehand  that  the  external  part  of  a  neuroma  is  permeable  to 


CLINICAL    TYPES  81 

regenerated  axis-cylinders,  whereas  its  internal  part  offers  an   insurmount- 
able barrier  to  them. 

We  shall  then  be  led,  along  the  lines  of  the  constitution  and  fascicular 
topography  of  the  nerve  trunks,  in  the  direction  of  a  fascicular,  rational 
and  economical  surgery. 

VI.— ASCENDING    NEURITIS 

Strictly  speaking,  ascending  neuritis  is  not  a  type  of  traumatic  nerve 
lesions,  it  is  a  complication  and  often  a  serious  one. 

It  is  characterised  by  the  fact  that  the  traumatised  nerve  not  only 
degenerates  rapidly  towards  its  peripheral  extremity,  but  undergoes  a  slow, 
progressive,  ascending  degeneration  of  its  central  segment. 

Ascending  neuritis  seems  due  to  the  progressive  ascent  in  the  nerve,  or 
the  sheath  of  the  nerve,  of  the  toxic  products  or  infectious  agents  of  the 
focus  of  the  wound. 

Fortunately  it  is  very  rare,  for  it  may  culminate  in  definite  degenera- 
tion of  the  nerve. 

Ascending  neuritis  has  most  frequently  as  its  starting  point  the  per- 
sistence of  an  osseous  focus  of  suppuration. 

It  is  characterised  by  very  acute  and  spontaneous  pains,  which  radiate 
over  the  entire  course  of  the  nerve  and  even  above  the  lesion.  These 
pains  are  often  sufficiently  acute  to  enable  the  patient  to  trace  on  his  limb 
the  course  of  the  nerve  involved. 

It  is  a  continuous  pain  with  paroxysmal  crises,  of  a  violent,  distressing 
and  intolerable  nature. 

The  nerve  is  painful  on  pressure,  not  only  at  the  level  of  the  nerve  and 
below  it  as  in  the  syndromes  of  irritation,  but  also  above  the  lesion. 

We  gradually  see  the  slow  ascent  of  this  pain  along  the  affected  nerve. 
Frequently  appearing  in  the  vicinity  of  its  termination,  it  ascends  to  the 
nerve  trunk  and  finally  reaches  the  origins  of  the  nerve.  It  invades  the 
plexuses  which  become  painful,  we  may  even  find  it  extending  ri^ht  to 
the  spinal  cord  and  spreading  to  the  nerves  of  the  opposite  side. 

We  likewise  note  the  ascending  advance  of  muscular  atrophy  and  of 
paralyses,  although  these  latter  are  usually  incomplete.  We  see  the  pro- 
gressive extension  of  the  area  of  cutaneous  anaesthesia  or  hyperesthesia. 

Slight  ascending  neuritis  may  stop  in  its  progress  and  may  retrogress, 
even  after  a  considerable  interval,  especially  when  we  have  been  able  to 
carry  out  energetic  disinfection  or  the  removal  of  the  initial  focus  which 
caused  it. 

Severe  ascending  neuritis,  however,  is  usually  continued  for  months 
and  sometimes  years  ;  it  seldom  stops  before  reaching  the  plexus  and  the 
spinal  cord  itself.  It  causes  pain,  atrophy,  and  disabilities  that  are  often 
permanent  ;  section  of  the  nerve  above  the  lesion,  amputation  of  the  limb 
itself,  to  which  one  is  sometimes  reduced,  are  not  always  sufficient  to  stop 

6 


82  NERVE   WOUNDS 

it  if  the  infectious  or  toxic  agent  has  already  gone  beyond  the  point  of 
section. 

Its  exact  nature  completely  baffles  us,  although  the  hypothesis  of  the 
ascent  of  infectious  germs  or  of  toxic  agents  in  the  nerve  trunks  or  in  their 
sheath  seems  very  probable.  We  are  almost  completely  helpless  in  its 
presence,  for  whilst  experiments  on  animals  show  that  it  can  be  stopped 
by  early  section  of  the  nerve  trunks,  this  is  a  solution  which  one  cannot 
adopt,  apart  from  altogether  exceptional  cases. 


APPENDIX 

PARALYSIS,    HYPERTONIA    AND    CONTRACTIONS   FROM    NEURITIS 

Slight  irritations  of  the  peripheral  nerves,  capable,  as  we  have  seen,  of 
inducing  fibrous  infiltrations  and  contractions  of  the  muscles,  mav  also 
induce  a  kind  of  muscular  hyper-excitability,  culminating  in  a  state  of 
hypertonia  or  even  of  genuine  contracture. 

We  meet  with  a  great  number  of  contractures  seemingly  paradoxical, 
frequently  succeeding  slight  injuries,  which  one  might  be  tempted  to 
regard  as  simple  hysterical  contractures.  But  if  we  minutely  study  these 
contractures,  we  note  the  presence  of  a  certain  number  of  characteristics 
indicating  the  existence  of  organic  lesion,  such  as  cyanosis,  low  tempera- 
ture, profuse  sweats,  trophic  disturbances  of  skin  and  nails,  sensory  dis- 
turbances clearly  defined,  slight  modifications  of  the  electrical  reactions 
and  mechanical  excitability  of  the.  muscles.  These  disturbances  have 
been  specially  studied  by  Babinski  and  Froment  who,  under  the  name 
of  "reflex  contractures,"  have  clearly  distinguished  them  from  simple 
functional  contractures. 

These  are  the  "  painful  contractures  "  described  by  Claude,  the  "  mains 
jigees"  of  H.  Meige  and  Mme  Ath.  Benisty,  the  " acro-contractures"  or 
"  acro-myotonies  "  of  Sicard. 

It  is  extremely  difficult  to  interpret  these  disturbances.  All  neurolo- 
gists recognise  the  existence  in  these  cases  of  the  slight  changes  studied  by 
Babinsky  and  Froment ;  they  admit  generally  that  these  changes  reveal 
the  existence  of  slight  organic  lesions  ;  some  regard  them  as  sympathetic 
or  reflex  disturbances,  others  as  the  result  of  slight  neuritis.  Most,  how- 
ever, refuse  to  admit  the  purely  organic  nature  of  these  paralyses  or 
contractures ;  they  interpret  them  as  functional  disturbances  grafted  on  to 
slight  organic  lesions.  It  is,  indeed,  illogical  and  abnormal  to  find  a  simple 
sprain  producing  a  paralytic  club-foot  or  a  permanent  contracture  of  the 
foot  ;  it  is  paradoxical  to  find  that  contracture  of  hand  or  arm,  following 
a  simple  fracture  of  the  radius  or  a  superficial  wound,  may  last  for  a  period 
of  eighteen  months. 


CLINICAL   TYPES 


83 


Amongst  these  accidents  of  a  complex  and  ill-defined  nature,  it  is  now 
possible  to  distinguish  a  very  clear  group  of  paralyses  and  especially  of 
contractures,  of  manifestly  nervous  origin,  provoked  by  slight  irritative 
lesions  of  a  peripheral  nerve. 

But  in  almost  all  cases  of  clearly  defined  neurites,  it  is  easy  to  prove  the 
existence  of  a  very  important  functional  factor. 

These  neuritic  paralyses  and  contractures  are  almost  always  functional 
associations.  Nerve  irritation  is  the  origin  of  the  disturbances  found  ;  it 
provokes  the  appearance  of  muscular  hypertonia,  of  pains  and  sensory 
disturbances,  of  trophic,  vaso-motor  and  secretory  symptoms.     But  in  most 


Fig.  24.. — Contracture  of  the  hand,  immobilised  in  extension  with  flexion  of  the  thumb  j 
perforating  wound  of"  fore-arm.  Almost  complete  anaesthesia  of  the  ulnar;  hypo- 
icsthesia  of  the  median.  Trophic  disturbances  of  nails  and  skin  ;  profuse  sweats. 
(Slight  neuritis  of  ulnar  and  median.) 

cases  it  is  the  permanent  immobilisation,  the  prolonged  inaction,  the  auto- 
suggestion of  impotence  and  the  moral  inertia  of  the  patient  that  intensify, 
amplify  and  prolong  these  disturbances  ;  it  is  the  dread  of  pain  that  immo- 
bilises into  a  state  of  paralysis  the  limb  affected  with  slight  neuritis,  it  is 
inaction  that  transforms  into  obstinate  contraction  the  neuritic  hypertonia 
of  the  muscles,  it  is  the  inertia  of  the  patient  that  enables  neuritis  to  pro- 
duce its  maximum  effect,  to  keep  up  the  vaso-motor,  thermal  and  trophic 
disturbances  which  we  find  in  these  cases. 

We  shall  study  more  specially  contractures  caused  by  neuritis,  which 
seem  particularly  frequent. 

***** 

The  first  thing  that  strikes  one  is  the  parodoxical  character  of  these 
contractures,  in  which  the  nerve  lesion  produces  the  exact  opposite  of  the 
usual  paralytic  syndrome. 

Sometimes  they  are  simple  states  of  muscular  hypertonia,  painless  and 
rather    easily    reducible.     To    passive    movements,    the    muscles    affected 


84 


NERVE   WOUNDS 


oppose  only  a  certain  elastic  resistance,  easily  overcome  :  when  they  are 
reduced,  we  frequently  notice  the  appearance  of  a  kind  of  muscular  tremor, 
comparable  to  the  epileptiform  tremor  of  the  foot.  Their  rigidity  becomes 
greater  during  active  movements  which  become  almost  impossible  for  the 
patient.     This  hypertonia  induces  a  permanent  posture  of  the  limb,  the 


Fig.  25. — Contracture  of  the  hand  in 
flexion,  after  eleven  months,  caused  by 
slight  lesion  of  the  ulnar  and  the 
median  above  the  elbow.  No  paralysis, 
normal  electrical  reactions.  Con- 
tracture mainly  of  the  interossei,  and 
contracture  of  the  palmar  fascia.  It  is 
possible  to  extend  the  hand  without 
much  diflictilty  ;  it  remains  extended 
without  pain  after  contracture  has  been 
overcome,  and  gradually  closes  again 
in  5  or  6  hours.  Almost  complete 
anesthesia  of  the  ulnar,  hypo-aesthesia 
of  the  median. 


fixity  of  which   is  further  increased  by  the  inaction  to  which  the  patient 
too  often  resigns  himself  and  which  ends  in  complete  loss  of  use. 

In  other  cases,  muscular  rigidity  produces  permanent  contractures, 
which  persist  for  months  and  produce  the  most  paradoxical  attitudes.  They 
offer  enormous  opposition  to  attempts  at  resistance.     Seldom   painful    at 


CLINICAL    TYPES 


85 


rest,  they  become  extremely  painful  when  an  attempt  is  made  to  overcome 
them,  and  this  very  pain  seems  to  increase  their  intensity. 

When   we  have  slowly  and  gradually  succeeded   in  overcoming  these 
contractures  and  bringing  back  the  limb  to  its  normal  position,  we  find  that, 


Fig.  26. — Contracture  of  the  hand  from  slight  lesion  of  the  ulnar  in  the  fore- 
arm.    (Contracture  of  the  interossei  and  of  the  hypothenar  eminence.) 

in  a  tew  minutes,  a  few  hours,  or  even  a  few  days,  the  muscles  contract 
anew  and  the  limb  gradually  resumes  its  original  posture. 

Many  of  these  contractures  are  gradually  intensified  ;  through  the  relax- 
ation of  the  antagonistic  muscles  and  articular  ligaments,  they  are  found 
by  degrees  to  adopt  the  most  unusual  postures. 

These  contractures  almost 
always  follow  on  slight  wounds  ; 
at  times  appearing  suddenly 
with  the  injury,  more  fre- 
quently coming  about  slowly, 
long  after  the  wound  is  healed, 
they  are  invariably  accompanied 
by  nearly  normal  electrical  re- 
actions ;  the  usual  symptoms  of 
nerve  lesions  are  either  scarcely 
perceptible  or  are  altogether 
absent. 

Still,  a  minute  study  enables 
us  to  detect  in  these  "con- 
tractures from  neuritis  "  a  com- 
plete series  of  symptoms  which 
combine  to  demonstrate  the 
existence  of  an  organic  factor  in  the  case. 

I.  The  contracted  muscles  frequently  show,  along  with  slight  atrophy, 


Fig 


— Contracture  of  the  hand  owing  to 
slight  lesion  of  the  ulnar  in  the  fore  arm.  The 
patient  can  bend  only  his  thumb,  index  and 
middle  ringers,  and  even  these  very  imperfectly. 
Passive  flexion  is  fairly  easy.  This  figure 
represents  the  maximum  of  flexion  possible. 
(Contracture  of  interossei  and  extensors.) 


86 


NERVE    WOUNDS 


a  state  of  mechanical  hyper-excitability  indicated  by  the  intensification  and 
slowness  of  the  idio-muscular  reflexes. 

Electrical  examination  sometimes  reveals  a  certain  slowness  of  con- 
traction in  the  shortened  muscles. 

Their  special  rigidity  and  the  muscular  tremor  provoked  by  attempts 
at  reduction  often  persist  during  slight  chloroform  anaesthesia.  For  instance, 
Babinski  and  Froment  have  succeeded  in  discovering  by  patellar  clonus 
under  anaesthesia,  hypertonia  of  the  contracted  quadriceps.  The  tendon 
reflexes  also  often  appear  intensified  during  anaesthesia. 


Fig.  28. — Contracture  of  the  hand. — 
Hypertonia  of  all  the  muscles  of  the 
hand.  The  hand,  at  first  contracted 
for  eight  months  in  complete  flexion, 
has  been  contracted  in  extension  after 
gradual  opening  of  the  fingers.  Fol- 
lowing on  suppurating  sore  of  the 
wrist,  acute  pains  in  the  course  of  the 
median,  musculo-spiral  and  even  a 
little  of  the  ulnar  just  above  the  elbow; 
hyperesthesia  in  the  area  of  the 
median  and  the  musclo-spiral.  (Pro- 
bable ascending  neuritis. ) 


These  contractures  are  frequently  accompanied  by  more  or  less  pro- 
nounced trophic  or  vaso-motor  disturbances,  and  by  secretory  disturbances 
in  some  cases. 

Generally  there  exists  a  cooling  of  hand  or  foot,  that  may  correspond 
to  a  fall  of  several  degrees  of  temperature. 

Frequently  there  are  profuse  sweats  which  sometimes  produce  actual 
maceration  of  the  epidermis,  and  appear  along  with  a  special  kind  of  red- 
ness of  the  skin,  clearly  localised  in  the  region  of  the  irritated  nerve. 

In  other  cases  we  have  dull  pallor  of  the  integuments,  with  dryness  of 


CLINICAL   TYPES 


87 


the  skin.  At  times,  there  is  slight  fibrous  infiltration  of  the  integuments, 
or  else  thinning  of  the  skin  which  assumes  the  aspect  of  onion  rind. 
Hypertrichosis  is  particularly  frequent. 

Then  we  have  nail  disturbances  :  their  dull  or  sometimes  striated 
appearance,  their  yellowish  hue  comparable  with  that  of  ivory,  the 
cutaneous  swellings  which  their  rapid  growth  raises  on  the  pulp  of  the 
fingers. 

Finally,  in  some  cases,  we  have  slight  contraction  of  the  palmar  or 
plantar  fasciae,  showing  the  similarity  of  these  cases  to  the  neuritic 
syndromes  we  have  already  investigated. 

3.  Almost  always  there  are  pronounced  sensory  disturbances. 

It  is  seldom  that  we  do  not  find  a  more  or  less  definite  hypo-aesthesia 


Fig.  29. — "Accoucheur's  hand"  due  to  contracture  of  the  muscles  or  the  hand  ;  after  a 
fall  producing  fracture  of  radius.  Thermal  and  vaso-motor  disturbances,  profuse 
sweats.  Hypoiesthesia  on  the  region  of  C6,  C7 — and  Di  (probable  wrench  of  the 
brachial  plexus). 

in  the  region  of  the  nerve  involved  ;    hyperesthesia,  on  the  other  hand, 
appears  less  frequently. 

Almost  always  we  find  in  the  nerve  itself  pain  on  pressure,  or  the 
presence  along  its  tract  of  provoked  formications,  which  show  slight 
irritation,  or  the  regeneration  in  it  of  some  injured  fibres. 

4.  We  must  insist  on  the  anatomical  character  of  the  changes  observed. 
These  contractures  are  generally  clearly  limited  to  the  region  of  the  nerves 
involved,  or  even  to  a  portion  of  their  area  in  case  of  partial  lesions. 
Sensory,  trophic  and  vaso-motor  disturbances  have  also  a  precise 
topography. 

In  contradistinction  to  hysterical  contractures,  states  of  neuritic  hyper- 
tonia are  "contractures  acquainted  with  anatomy." 

***** 

These  contractures  due  to  neuritis  may  be  found  in  the  region  of  all 
the  motor  nerves. 


88 


NERVE    WOUNDS 


They  would  seem,  however,  to  hzve  been  found  with  particular 
frequency  in  the  region  of  the  ulnar  ;  hypertonia  of  the  interossei,  affect- 
ing all  these  muscles,  or  only  certain  of  them,  produces  contractures  of 
hands  and  ringers  ;  association  of  the  median  causes  the  appearance  of  the 
"accoucheur's  hand,"  described  by  Babinski,  or  flexed  contraction  of  hand 
and  fingers. 

The  musculo-cutaneous  may  be  involved  in  certain  contractures  of  the 
biceps.      We   have   seen    even   the   musculo-spiral    induce  contraction    in 

hyper-extension      of     hand      and 
fingers. 

Likewise  with  the  lower  limb, 
the  anterior  crural  nerve  seems 
responsible  for  certain  contractions 
of  the  quadriceps,  just  as  the 
sciatic  is  capable  of  provoking 
certain  contractures  of  the  posterior 
muscles  of  thigh,  calf  and  foot. 
We  find  pes  equinus  and  club-foot 
from  contracture  originating  in 
hypertonia  through  slight  irritation 
of  the  sciatic  or  its  branches. 


Lesions  of  the  plexuses  would 
also  seem  as  though  they  must 
have  been  involved  in  certain  cases. 
We  have  observed,  for  instance, 
a  case  of  wrench  of  the  sacral 
plexus,  with  hypo-a^sthesia  in  the 
region  of  the  fifth  lumbar,  first 
and  second  sacral ;  there  existed 
a  state  of  obvious  muscular  hyper- 
tonia of  the  posterior  muscles  of 
the  thigh,  as  well  as  of  the  muscles 
of  leg  and  foot.     In  contractures 


Fig.  30. — Contracture  of  extensors  of  hand 
and  fingers  ;  following  on  a  wound  of  the 
hand  crossing  the  thenar  eminence  ;  with 
prolonged  suppuration.  Progressive  ac- 
centuation for  a  period  of  sixteen  months. 
Acute  pains  in  the  course  of  the  nerves  of 
the  fore-arm,  particularly  of  the  musculo- 
spiral.  (Probable  ascending  neuritis  of  the 
musculo-spiral.) 

of    hand   and  arm   also  are  often 

found    sensory  disturbances    with    root-distribution, — disturbances   which 

indicate  the  irritation  or  wrenching  of  the  cervical  roots. 

Whilst  in  certain  cases  contracture  from  neuritis  is  shown  in  the 
domain  of  an  injured  nerve,  there  are  other  more  disturbing  cases  where  the 
seat  of  the  wound  seems  in  no  way  to  justify  the  appearance  of  neuritic 
troubles.  These  are  particularly  cases  in  which  wounds  of  fingers,  hand 
or  foot  are  accompanied  by  extensive  contractions. 

These  are  slight  ascending  neurites,  which  spring  from  infection  of  the 
wound.     Their  presence   is  revealed   principally  by  pain  and   formication 


CLINICAL    TYPES  89 

in  the  nerve  trunks  on  pressure  over  a  larger  or  smaller  part  of  their  course 
above  the  wound,  by  hypo-atsthesia  or  hyperesthesia  of  their  cutaneous 
region,  by  atrophy  of  the  muscles  they  supply,  and  often  exaggeration  of 
the  muscular  and  tendon  reflexes  of  their  entire  motor  region. 

There  is  another  cause  of  contraction  from  neuritis  :   frost-bite. 

Some  forms  of  frost-bite  are  characterised  by  localised  neuritis  of  the 
frost-bitten  extremities.  Sclerous  infiltration,  trophic  disturbances  of  skin 
and  nails,  fascial  contractions,  the  acute  pain  provoked  by  pressure  on  the 
muscular  bellies,  paralysis  with  faradic  excitability  of  the  muscles,  are  all 
so  many  proofs  of  the  neuritic  character  of  these  cases.  Whilst,  however, 
these  trophic  and  paralytic  disturbances  characterise  severe  cases  of  frost- 
bite, slight  cases  of  neuritis  may  be  shown  by  muscular  hypertonia. 

We  have  observed  several  cases  of  contraction  appearing  on  frost- 
bitten limbs  without  any  wound,  accompanied  bv  the  same  sweats,  trophic, 
vaso-motor  and  slight  sensory  disturbances.  Their  more  diffused  distribu- 
tion is  often  irregular  ;  for  instance,  we  find  jumbled  together  zones  of 
hypo-aesthesia,  of  hyper-aesthesia,  and  of  almost  normal  sensibility  ;  this  is,  so 
to  speak,  neuritis  in  islets,  but  the  state  of  muscular  hypertonia  is  as  clearly 
defined  as  in  neuritis  over  a  systematised  region. 

***** 

However  clear  the  organic  signs  noted  in  most  cases,  manifestly  there 
often  exists  in  the  genesis  of  those  contractions  an  important  functional 
factor. 

They  scarcely  ever  appear  except  in  patients  who  are  resigned  to  them, 
and  are  flagrantly  inactive  ;  they  persist  for  an  unconscionable  time  ;  treat- 
ment improves,  but  rest  and  convalescence  aggravate  them  ;  we  even  find 
certain  of  these  contractions,  almost  cured  by  electrical  treatment  and  daily 
mobilisation,  progressively  reappear  during  convalescence.  On  the  other 
hand,  we  may  find  others  disappearing  under  the  effect  of  treatment,  whilst 
all  the  neuritic,  vaso-motor,  secretory  and  trophic  disturbances,  which 
seemed  to  give  them  birth,  persist. 

It  would  therefore  seem  that  in  most  cases  neuritis  cannot  produce 
such  contractions  without  the  aid  of  the  prolonged  immobilisation  and 
muscular  disuse  which  aggravate  its  consequences.  We  have  been  able  to 
give  a  rather  curious  demonstration  of  this  ;  out  of  fifteen  patients  suffering 
from  contraction  due  to  irritation  of  the  ulnar,  with  immobilisation  of  the 
interossei  and  of  the  hypothenar  eminence,  we  found  only  two  cases  where 
there  was  contraction  of  the  adductor  pollicis  ;  the  other  thirteen  patients 
had  saved  the  thumb  and  succeeded  in  retaining  its  movements  intact  ; 
probably  with  a  little  effort  and  patience  they  might  have  avoided  con- 
traction of  the  other  fingers,  not  so  necessary  for  everyday  use. 

Treatment  of  contractions  from  neuritis  is  a  particularly  delicate 
matter.     Energetic  mobilisation  accentuates  them  ;  massage  and  electrical 


9o 


NERVE   WOUNDS 


stimulation  are  painful  at  times  and  unpleasant  to  bear  ;  and  yet  it  is 
impossible  to  allow  the  contraction  to  continue,  the  more  so  as  there  is 
almost  always  a  tendency  gradually  to  become  more  and  more  inactive 
from  relaxation  of  the  antagonists  and  of  the  articular  ligaments. 


Fig.  31.— Club-foot  from 
contraction  following  on 
sprain,  after  eighteen 
months  !  In  the  right 
foot  is  contraction  of  all 
the  plantar  muscles  as  well 
as  contraction  of  the 
tibialis  posticus  which 
causes  club-foot.  Dis- 
turbances of  sensibility 
revealing  slight  neuritic 
lesion  of  the  external 
popliteal  and  more  par- 
ticularly of  the  internal 
popliteal  nerves.  (Com- 
pare with  the  healthy  left 
foot.) 

We  have  been  very  successful  in  bringing  about  gentle,  progressive 
and  continuous  mobilisation  by  the  aid  of  improvised  appliances.  An 
associated  treatment  consists  of  hot  baths  with  faradic  current  ;  these  give 
the  best  results.  Indeed,  a  very  hot  and  prolonged  bath  causes  these 
contractions  to  become  remarkably  supple  ;  if  there  is  introduced  into  the 
bath  a  moderate  faradic  current,  interrupted  by  the  metronome,  its  vaso- 
dilator action  is  further  increased,  at  the  same  time  very  gentle  massage  is 


CLINICAL    TYPES 


91 


applied  to  the   contracted   muscles  ;  an    undulatory  faradic  current  would 
certainly  be  even  better. 

One  condition,  however,  is  indispensable  in  the  cure  of  these  cases  ; 
perseverance  and  good  will  on  the  part  of  the  patient.  Indeed,  the  treat- 
ment of  these  contractions  is  long,  wearisome  and  often  painful.  Too 
frequently  the  patient  becomes  discouraged,  resigned  to  the  disuse  of  his 
contracted  limb,  and  then   he  ceases  to  contribute  to  the  treatment  the 


Fig.  32. — Claw-like  contraction  of  the  feet  following 
on  frost-bite,  with  signs  of  slight  neuritis  and 
cutaneous  hypoitsthesia. 

main   factor,  after   all — his    personal   quota   of 
exercises  and  active  movement. 

It  must  not  be  forgotten  that,  though  slight 
neuritis  is  the  initial  cause  of  contraction,  it  is 
frequently  disuse,  inertia  or  indifference  on  the 
part  of  the  patient  that  enables  it  to  get  a  hold 
on  him.  Though  this  contraction,  at  the  end 
of  several  months,  has  become  so  irreducible 
as  to  prevent  all  voluntary  movement,  such  is 
not  the  case  when  it  first  shows  itself.  Probably  in  most  cases,  daily 
exercise,  patient  mobilisation,  sincere  efforts  to  recover  the  use  of  the  limb 
would  rapidly  have  dispelled  contraction. 

We  discover  this  by  noting  the  various  results  of  treatment  according 
to  the  moral  condition  of  the  patient.  Whereas  some  rapidly  improve  by 
a  treatment  they  follow  with  interest,  others  submit  to  it  without  con- 
fidence and  unwillingly,  they  take  no  interest  in  the  results,  make  no 
effort  of  their  own,  and,  quite  unconcerned,  allow  contraction  to  follow  its 
course.  The  treatment,  therefore,  of  these  disturbances  essentially  involves 
a  moral  factor,  just  as  their  pathogeny  introduces  an  important  functional 
factor. 


CHAPTER   V 

GENERAL  DIAGNOSIS  OF  PERIPHERAL  NERVE 

LESIONS 

We  shall  not  dwell  long  on  the  differential  diagnosis  of  peripheral  trau- 
matic paralysis,  for  in  the  course  of  our  clinical  sketch  of  the  subject 
under  consideration,  we  have  drawn  attention  to  the  main  errors  possible. 

i.  It  must  be  remembered  that  this  study  is  confined  to  injuries  of  the 
peripheral  nerves  from  wounds,  so  that  we  may  at  once  eliminate  : 

(i)  Central  paralysis,  cortical  monoplegias,  following  traumatisms  of 
skull  or  brain — characterised  moreover  by  the  absence  of  atrophy  and 
electrical  disturbances,  exaggeration  of  the  reflexes,  progressive  change 
to  a  spastic  state,  predominence  of  paralysis  or  of  anaesthesia  at  the  peri- 
phery of  the  limb,  absence  of  the  peripheral  type  of  distributing  anaesthesia. 

(2)   Paralysis  by  cord  lesions,  compression,  crushing,  or  hematomyelia. 

The  same  spastic  symptoms,  indicative  of  lesion  of  the  pyramidal  tract, 
characterise  paralysis  related  to  cord  lesions. 

Compressions  of  the  cord  are  nevertheless  accompanied  by  compression 
of  the  roots,  so  that  we  find,  in  addition  to  the  spastic  signs  of  spinal  cord 
paraplegia,  signs  of  paralysis  of  the  peripheral  type  which  correspond  to 
the  roots  included  in  the  compression. 

On  the  other  hand,  hematomyelias  which  sometimes  follow  a  simple 
vertebral  concussion  or  a  sort  of  gaseous  embolus  by  decompression 
(paralysis  from  shell  shock)  are  often  limited  to  the  grey  matter  of  the 
cord.  They  cause  in  this  case,  from  a  lesion  of  the  anterior  horns, 
paralyses  of  the  peripheral  type,  analogous  to  those  of  poliomyelitis.  For 
instance,  we  may  meet  with  hematomyelias  limited  to  the  first  and  second 
sacral  segments,  which  are  somewhat  similar  to  paralysis  of  the  sciatic. 

Almost  invariably,  however,  the  history  of  a  spinal  injur)',  the  greater 
diffusion,  at  first,  at  all  events,  of  the  paralytic  signs,  and  the  habitual 
coexistence  of  some  slight  indications  of  pyramidal  irritation  are  all 
elements  which  help  the  diagnosis. 

On  the  other  hand,  these  hematomyelias  are  often  accompanied  by 
lesions  of  the  posterior  horns,  with  disturbances  of  sensation  ;  but  these 
disturbances  are  arranged  with  root  distribution  ;  they  have  neither  the 
intensity  nor  the  precise  limitation  of  peripheral  anaesthesias  ;  almost  in- 
variably they  are  dissociated,  and  then  we  note  along  with  a  more  or  less 


DIAGNOSIS   OF   PERIPHERAL   NERVE    LESIONS       93 

marked  diminution  of  thermal  and  painful  sensibilities,  a  relative  preserva- 
tion of  tactile  sensibility  and  an  almost  complete  integrity  of  deep 
sensibility. 

(3)  Peripheral,  spontaneous,  progressive  polyneurites  ;  these  have 
naturally  all  the  signs  of  peripheral  paralyses :  flaccidity,  hypotonia, 
muscular  atrophy,  and  disturbances  of  electrical  reactions^  they  often  show 
sensory  disturbances  or  pain  and  the  fibrous  contractions  of  nerve  irritation  ; 
they  are  almost  always  bilateral  and  symmetrical. 

(4)  Root  inflammation,  caused  by  inflammation  of  the  meningeal 
sheaths  surrounding  the  spinal  nerve  roots.  Almost  always  sensory  or 
sensory-motor,  seldom  purely  motor,  inflammation  of  the  nerve  root  of 
lower  or  upper  limb  are  alike  spontaneous  and  progressive.  They  often 
owe  their  origin  to  syphilis,  sometimes  to  tuberculosis,  more  rarely  to 
infectious  meningitis  such  as  cerebro-spinal  meningitis.  The  root 
distribution  of  motor  and  sensory  disturbances,  the  radiating  pain  provoked 
by  coughing  and  sneezing,  the  signs  of  concomitant  meningeal  irritation 
revealed  by  lumbar  puncture,  generally  enable  us  to  recognise  them. 

2.  The  most  important  diagnosis  concerned  with  the  group  of  func- 
tional paralyses.  They  are  extremely  frequent,  and  we  continually  find  it 
necessary  to  differentiate  them  from  peripheral  nerve  lesions. 

This  matter  of  false — or  rather  artificial — paralyses  is  extremely 
important. 

(1)  Following  on  war  wounds,  there  are  found  typical  hysterical 
paralyses,  the  main  characteristics  of  which  must  be  remembered. 

At  first  they  are  almost  always  striking  by  reason  of  their  paradoxical 
nature,  the  evident  disproportion  between  the  importance  or  the  site  of 
the  wound  which  is  frequently  a  slight  one,  and  the  extent  of  the  paralytic 
disturbances. 

They  are  widespread  and  absolute  ;  nor  is  there  found  in  the  patient 
any  attempt  at  compensation. 

They  correspond  to  no  definite  anatomical  region,  but  attack  an  entire 
limb  or  segment  of  a  limb  ;  they  do  not  paralyse  a  movement  but  rather 
a  function. 

Almost  invariably  they  are  accompanied  by  widespread,  absolute  para- 
doxical anaesthesia,  corresponding  to  no  nerve  region  but  rather  affecting 
a  whole  line  or  segment  of  a  limb.  These  are  segmentary  anaesthesias, 
clearly  limited  by  a  circular  line  ;  glove,  boot,  leg  of  mutton,  etc.,  types  of 
anaethesia. 

They  are  not  associated  with  muscular  atrophy,  loss  of  tone,  dis- 
turbances of  the  reflexes  or  trophic  disturbances. 

Still,  we  see  that  there  occurs  in  the  long  run  a  sort  of  muscular  hypo- 
tonia from  disuse  ;  we  also  at  times  note  a  slight  cyanosis  which  may  be 
due  to  prolonged  disuse  or  to  the  dependent  posture. 

The  electrical  reactions  of  nerves  and   muscles  are  normal  or  almost 


94  NERVE   WOUNDS 

normal.  It  is  possible  to  detect  a  slight  hypo-excitability  in  muscles  long 
paralysed. 

These  paralyses  are  almost  always  accompanied  by  a  special  frame 
of  mind,  characterised  by  an  absence  of  effort. 

There  appears  to  exist  so  absolute  a  conviction  of  paralysis,  so  great 
a  certainty  of  its  incurability,  that  the  patient  comes  to  take  no  interest  in 
his  paralysed  limb,  he  does  not  seem  anxious  to  recover. 

And  yet  these  paralyses  may  be  rapidly  and  thoroughly  cured  if  the 
patients  are  placed  under  appropriate  treatment,  the  main  elements  of 
which  are  isolation,  patient  psychotherapy,  energetic  faradisation  and  motor 
re-education. 

Apart,  however,  from  these  well-established  hysterical  paralyses,  there 
are  many  functional  paralyses  which  must  be  recognised. 

(2)  Paralyses  from  prolonged  inaction  or  loss  of  the  habitual  muscular 
movements. 

As  a  sequence  of  muscular  wounds,  fractures  necessitating  prolonged 
immobilisation,  tendon  lesions  or  articular  injuries,  we  may  have  pseudo- 
paralyses  due  to  prolonged  disuse  of  the  muscles.  These  are  caused  by 
dread  of  pain  or  by  a  sort  of  loss  of  the  habitual  use  of  the  muscle,  or  even 
by  the  simple  conviction  of  incapacity. 

Nevertheless,  electrical  reactions  are  normal ;  faradisation  of  the  muscle 
provokes  its  energetic  contraction  and  demonstrates  to  the  patient  the 
possibility  of  movement  ;  faradic  treatment,  energetic  if  need  be,  rapidly 
effects  a  cure. 

(3)  Pseudo-paralyses  from  pain. 

With  these  cases  must  be  compared  muscular  incapacity  provoked  by 
pain,  the  wounded  man  ceasing  to  contract  his  muscles. 

(4)  Pseudo-paralyses  from  contraction  of  the  antagonists,  rendering 
movement  impossible. 

(5)  Functional  paralyses  from  prolongation  of  organic  paralysis. 

In  certain  cases  we  find  that  paralysis  is  protracted  when  caused  by 
nerve  lesion  even  after  the  nerve  has  regained  its  functions  and  the 
electrical  reactions  have  become  normal. 

These  functional  paralyses  are  after  all  only  an  exaggeration  of  muscular 
incompetence,  seen  in  wounded  men  who  recover  their  lost  function. 

They  are  specially  frequent  after  nerve  lesions  accompanied  by  nerve 
irritation,  because  in  these  cases  the  dread  of  pain  and  a  certain  degree  of 
fibrous  transformation  of  the  muscles  are  associated  with  the  auto-suggestion 
of  incompetence. 

Faradisation  again  provides  the  means  of  diagnosis  and  treatment. 

(6)  Functional  paralyses  from  anaesthesia. 

In  these  cases,  the  role  of  auto-suggestion  is  even  more  manifest.     We 
are  now  concerned  with  paralyses  following  on  lesion  of  a  sensory  nerve. 
The  most  frequent  example  is  afforded  by  lesion  of  the  median  at  the 


DIAGNOSIS   OF   PERIPHERAL   NERVE   LESIONS       95 

lower  third  of  the  fore-arm  ;  this  nerve  has  become  almost  entirely  sensory, 
having  to  supply  only  the  motor  twigs  to  the  thenar  muscles  and  to  the 
lumbricales  ;  now,  we  find  an  inexplicable  paralysis  of  flexion  in  the  first 
three  fingers.  The  patient,  noticing  that  there  is  anaesthesia  in  hand  and 
fingers,  concludes  that  they  are  powerless  and  ceases  to  move  them. 

The  same  thing  is  met  with  in  the  lower  lesions  of  the  anterior  tibial 
or  of  the  musculo-cutaneous. 

Here,  too,  faradisation  shows  integrity  of  the  muscles  and  the  functional 
nature  of  the  paralysis. 

3.  In  a  third  group  we  may  place  the  osseous,  muscular,  and  tendon 
lesions. 

(1)  Paralyses  from  pseudarthrosis. 

(2)  Pseudo-paralyses  resulting  from  muscular  destruction. 

(3)  Pseudo-griffis  produced  by  muscular  or  tendon  contraction.  For 
instance,  the  ulnar  pscudo-griff~e  produced  by  contraction  of  the  flexors  of 
the  last  two  fingers  or  the  pseudo-paralysis  of  the  external  popliteal  nerve, 
resulting  from  fibrous  contraction  of  the  calf  or  of  the  Achilles  tendon, 
with  production  of  pes  equinus. 

(4)  Pseudo-paralyses  of  hand  or  fingers  produced  by  cicatricial  adhesion 
of  the  tendons,  or  following  on  the  tendon  adhesions  which  nerve  irritations 
produce. 

(5)  Reflex  muscular  atrophies,  following  on  a  neighbouring  fracture  or 
arthritis  or  on  simple  contusion  of  the  muscle. 

(6)  Pseudo-paralyses  from  hypotonia  and  muscular  stretching. 

The  type  of  these  is  furnished  by  the  pseudo-musculo-spiral  paralysis 
following  on  hypotonia  and  stretching  of  the  extensors  of  the  wrist.  It 
may  be  found  following  contusion  of  the  fore-arm,  after  lesion  or  section  of 
the  tendons,  producing  a  sort  of  accidental  tenotomy,  or  even  as  the 
consequence  of  a  prolonged  defective  posture.  For  instance,  we  have  found 
it  following  hysterical  paralysis  of  the  hand  which  began  ten  months 
previously  ;  in  another  case  after  fracture  of  the  humerus  and  the  wearing 
for  six  months  of  a  sling  supporting  the  fore-arm  and  allowing  the  hand  to 
droop  at  the  wrist  ;  in  these  two  cases,  voluntary  raising  of  the  hand  by  the 
lengthened  extensors  of  the  wrist  was  possible,  though  at  the  cost  of  so  great 
an  effort  that  the  hand  permanently  retained  the  posture  of  musculo-spiral 
paralysis  and  the  patient  had  given  up  holding  it  extended. 

This  muscular  hypotonia  caused  by  a  vicious  posture  is  a  distinct  factor 
in  artificial  prolongation  of  musculo-spiral  paralysis.  It  proves  the  necessity 
in  this  paralysis  of  an  apparatus  to  keep  the  hand  permanently  extended. 

Muscular  hypotonia  is  also  accompanied  by  almost  normal  electrical 
reactions  ;  it  is  cured  after  a  somewhat  prolonged  faradic  treatment  ;  in 
extreme  cases,  plication  or  shortening  of  the  tendons  may  even  be 
indicated. 

(7)  Contractions,  whether  the  result  of  muscular   irritation,  defensive 


96  NERVE    WOUNDS 

immobilisation,  a  prolonged  posture  or  a  simple  hysterical  manifestation, 
occasionally  produce  postures  which  might  be  mistaken  for  those  of 
paralysis. 

Especially  may  they  be  mistaken  for  nerve  irritations  and  fibrous 
infiltration  of  the  muscles  or  the  accompanying  tendon  contraction. 

It  is  fairly  easy  to  recognise  the  elastic  resistance  of  contractions  to  the 
attempts  at  mobilisation,  very  different  from  the  fibrous  resistance  of  the 
contracted  muscles.  These  contractions  disappear  under  anaesthesia.  Still, 
we  have  seen  that  very  often  they  had  as  their  initial  cause  a  slight  nerve 
irritation. 

4.  Ischsemic  paralysis. — Ischaemic  paralysis,  resulting  from  vascular 
obliteration  is  sometimes  most  difficult  to  distinguish  from  paralysis  caused 
by  nerve  lesions,  and  especially  from  syndromes  of  nerve  irritation  shown 
by  fibrous  contractions,  tendon  adhesions  and  griffe  postures. 

Ischemic  paralysis  is  sometimes  found  following  ligature  or  thrombosis 
of  the  great  arteries,  such  as  the  axillary,  the  sub-clavian,  the  brachial,  the 
femoral  or  the  popliteal  ;  it  may  also  appear  after  dressings  and  especially 
after  bandages  too  tightly  applied. 

It  is  essentially  characterised  by  ischaemia  with  cyanosis,  cooling  and 
trophic  disturbances  of  the  wounded  limb.  There  is  nothing,  however, 
more  variable  than  the  extent  of  these  disturbances,  with  like  lesions,  in 
different  patients. 

Whereas  the  majority  of  normal  subjects,  after  ligature  of  the  axillary 
or  the  sub-clavian,  for  instance,  simply  present  fleeting  ischaemic  disturbances 
of  the  hand,  with  the  same  lesion,  others  show  marked  signs  of  permanent 
ischemia,  generally  limited  to  the  hand  though  sometimes  extending  over  a 
considerable  segment  of  the  upper  limb. 

Ligature  also  of  the  femoral  or  popliteal  may,  according  to  the  patient, 
be  well  borne  or  may  provoke  the  appearance  of  ischaemic  paralysis  of  the 
foot  or  even  of  the  leg. 

These  differences  of  ischaemic  disturbances,  considerable  in  extent  and 
intensity  are  rather  difficult  to  interpret.  Probably  the  previous  state  of 
the  peripheral  arteries,  the  ease  or  difficulty  of  arterial  substitutions  by 
collateral  circulation,  and  perhaps  especially  the  nerve  lesions  associated 
with  the  arterial  lesions,  play  an  important  role  ;  nevertheless  the  problem 
of  the  pathogenesis  of  ischaemic  paralysis  is  not  completely  solved. 

At  all  events,  we  may  describe  two  phases  that  occur  in  the  evolution  of 
this  syndrome. 

In  the  first  phase  there  is  only  an  cedematous  infiltration  of  the  affected 
limb,  together  with  cyanosis  and  cooling. 

In  the  second,  after  an  average  of  two  to  three  months,  we  see  the 
fibrous  transformation  of  this  oedema. 

This  progressive  sclerous  infiltration,  which  makes  the  sub-cutaneous 
cellular  tissue  puffy,  invades  the  dermis,  contracts  the  muscles,  hardens  the 


DIAGNOSIS   OF   PERIPHERAL    NERVE    LESIONS       97 

aponeuroses,  submerges  the  tendons  and  synovial  sheaths  in  a  veritable 
fibrous  mass,  gives  the  tissues  a  woody  consistence  and  finally  transforms 
the  hand  into  a  kind  or  fibrous  bat. 

All  the  movements  are  suppressed  or  considerably  reduced  by  fibrous 
immobilisation  ;  the  glossy  skin,  desquamating  here  and  there  in  broad 
scales,  without  papillary  crests  and  reliefs,  is  cold  and  purple,  sometimes  a 
shining  red  ;  the  deformed,  cracked,  curved  nails  take  on  the  appearance  of 
shapeless  claws ;  the  bones  become  extremely  decalcified  ;  the  wood)' 
contraction  of  all  the  tissues  produces  wide-spread  atrophy  of  the  limb,  the 
fingers  have  a  fusiform  appearance  ;  the  osseous  projections,  the  prominence 
of  muscles  or  tendons,  the  cutaneous  creases,  the  articular  swellings 
disappear  and  become  atrophied,  submerged  in  the  progressive  fibrous 
infiltration. 

With  this  special  and  charactistic  appearance  are  associated  certain  signs. 

1.  Ischemic  paralysis  is  accompanied  by  the  disappearance  or  consider- 
able diminution  of  the  radial  pulse  in  the  case  of  the  hand,  of  the  dorsalis 
pedis  artery  and  of  the  tibialis  posticus  in  the  case  of  the  foot. 

2.  The  arterial  blood  pressure  undergoes  similar  diminution.  Whereas, 
for  instance,  we  find  by  Pachon's  oscillometre  an  antibrachial  pressure  of 
16-8  on  the  healthy  side,  we  shall  find  on  the  affected  side  a  pressure  of 
1 0-8,  or  of  9-8  shown  by  extremely  feeble  oscillations.  In  ischaemic  paralysis 
of  the  entire  lower  limb  following  on  the  obliteration  of  the  common  iliac, 
we  have  even  found  an  entire  absence  of  blood  pressure  or  of  the  slightest 
oscillation. 

Still,  in  certain  cases  of  ligature  of  the  axillary,  we  meet  with  consider- 
able diminutions  of  pressure,  without  serious  ischaemic  disturbances. 

3.  Ischemic  paralysis  is  almost  always  painful,  accompanied  by 
spontaneous  pains  with  such  characteristics  as  burning,  formication,  or 
unpleasant  tingling. 

Deep  pressure,  the  contact  of  heat  and  especially  of  cold,  are  often 
very  painful.  All  the  same,  there  are  ischaemic  paralyses  almost  free  from 
pain. 

4.  In  contrast  with  this  painful  sensibility  which  mainly  appears  to  be 
deep-seated,  we  usually  observe  considerable  anaesthesia  or  hypo-aesthesia 
of  the  skin,  affecting  without  dissociation  all  the  superficial  sensations, 
tactile,  painful,  thermal. 

Anaesthesia  predominates  at  the  extremity  of  the  limb  and  gradually 
decreases  towards  its  origin  ;  consequently  it  has  a  segmentary  topography. 

5.  The  electrical  reactions  of  the  infiltrated  muscles  are  profoundly 
disturbed.  We  may  find  tvpical  reactions  of  degeneration,  and  particularly 
enormous  hypo-excitability,  sometimes  even  the  abolition  of  all  electrical 
excitability  ;  this  is  rather  the  syndrome  of  fibrous  transformation  of  the 
muscles  ;  the  muscles  react  only  to  a  very  intense  current,  but  we  do  not 
note  any  polar  inversion  ;  often,  too,  stimulation  of  the  nerve  at  a  distance 
provokes  the  movements  more  readily  than  does  excitation  of  the  muscle. 

7     • 


98  NERVE   WOUNDS 

It  is  often  difficult  to  diagnose  these  ischaemic  disturbances,  not  from 
simple  paralyses  by  nerve  section  or  compression,  but  more  especially  from 
muscular  contractions,  trophic  disturbances  and  fibrous  griffes  of  nerve 
irritations. 

Moreover,  the  association  of  nerve  lesions  with  arterial  obliterations  is 
very  frequent ;  the  median  and  ulnar  nerves,  with  the  brachial  artery  ;  the 
popliteal  artery,  and  the  internal  popliteal  nerve  are  very  often  affected  by 
one  and  the  same  wound  ;  it  may  be  that  the  association  of  nerve  lesions 
is  an  important  factor  in  ischaemic  paralysis.  In  several  cases  of  ischaemia 
from  lesion  of  the  brachial,  involving  the  median  and  the  ulnar,  we  have 
seen  ischaemic  disturbances  becoming  enormously  increased  in  the  region 
of  the  affected  nerve. 

Bonamy  and  Verchere  have  reported  a  very  interesting  case  in  which 
ischaemia  of  the  hand  resulting  from  lesion  of  the  axillary  was  accompanied 
by  gangrene  of  the  hand  and  fingers  in  the  region  of  the  musculo-spiral, 
which  was  itself  slightly  injured.* 

Nevertheless,  in  a  general  way,  the  diagnosis  of  ischaemic  disturbances 
and  nerve  lesions  may  easily  be  made  along  the  following  general  lines  : — 

We  find  in  ischaemic  paralysis  no  peripheral  nerve  topography  what- 
soever. 

On  the  other  hand,  the  distribution  of  ischaemic  disturbances  is 
essentially  segmentary  and  centrifugal. 

All  disturbances,  cyanosis,  cooling,  fibrous  infiltration  and  anaesthesia  are 
preponderant  at  the  extremity  of  the  limb  ;  they  gradually  and  regularly 
diminish  as  we  approach  its  root. 

Finally,  the  diagnosis  of  ischaemic  paralyses  is  far  from  being  as  favour- 
able as  that  of  the  peripheral  nerve  lesions.  These  paralyses  are  severe 
and  often  incurable  lesions,  producing  permanent  incapacity. 

Still,  this  principle  must  not  be  set  up  absolutely,  for  in  certain  cases 
a  well-conducted  and  sufficiently  prolonged  treatment  by  means  of  hot 
baths,  permanent  hot-wrappings,  massage,  mobilisation  and  galvano-faradic 
baths  may  cause  rapid  retrogression  of  the  symptoms.  For  months  and 
even  years,  these  patients  are  capable  of  progressive  improvement  which 
at  times  surpasses  the  most  sanguine  hopes  and  expectations. 

*  Bonamy  and  Verchere.      "A  Case  of  Gangrene  of  the   Fingers  and   Hand  in  the  Region  of 
the  Musculo-spiral."     Societe  des  Chirurgiens  de  Paris,  21  May,  191 5. 


PART    II 
UPPER    LIMB 


CHAPTER    VI 

MUSCULO-SPIRAL   NERVE 

Paralysis  of  the  musculo-spiral  nerve  is  by  far  the  most  frequent ;  for  not 
only  may  the  nerve  be  affected  directly  like  the  other  nerves  of  the  upper 
limb,  but  it  is  very  often  surrounded  and  compressed  in  the  callus  of 
fractures  of  the  humerus  ;  it  may  also  be  accidentally  compressed  at  the 
level  of  the  axilla  by  pressure  of  crutches  (crutch  palsy)  or  on  the  posterior 
surface  of  the  arm  by  pressure  of  a  sharp  edge  during  deep  sleep  (Saturday 
night  palsy). 

ANATOMY  OF   THE   MUSCULO  =  SPIRAL   NERVE 


Anterior  aspect 


Posterior  aspect. 


The  musculo-spiral  nerve,  along  with  the  circumflex,  has   its   origin 
from  the  posterior  cord 
of  the  brachial  plexus. 

It  crosses  the  arm- 
pit behind  the  vasculo- 
nervous  bundle  ;  then 
it  plunges  obliquely 
towards  the  posterior 
part  of  the  arm  and 
describes  round  the 
diaphysis  of  the  hume- 
rus the  spiral  semi- 
circle which  brings  it 
over  the  external  sur- 
face of  this  bone. 
Along  this  course  it  ap- 
pears on   the  posterior 

surface  of  the  humerus  cy\    |w      FlGS#  33  and  3+._Course  of  i 
in  the  space  comprised      fflljnBw  musculo-spiral  nerve, 

between  the  inner  and  (diagrammatic), 

outer  heads  of  the  triceps  and  covered  by  its  long  head. 

After  passing  round  the  humerus,  the  musculo-spiral  appears  on   the 


100 


NERVE   WOUNDS 


external  border,  then  on  the  antero-external  surface  of  this  bone,  lying 
on  the  fibres  of  origin  of  the  brachialis  anticus.  In  its  spiral  tract  round 
the  humerus  it  is  very  often  affected  by  fractures  of  this  bone  or  surrounded 
by  callus  formation. 

It  descends  into  the  muscular  interspace  separating  the  supinator  longus 
from  the  biceps,  right  to  the  line  of  the  crease  of  the  elbow. 


Br.  to  the  teres  minoi 
Cut.  br.  to  shoulde 

Musculo-spiral  nerve 
Br.  to  long  head  of  triceps 

Br.  to  inner  head  of  triceps 


Br.  to  outer  head  of  tricep 
and  anconeus 


Br.  to  inner  head  of  triceps 
(ulnar  collateral) 


Ulnar  nerve 


Br.  to  anconeus  If 


Circumflex  nerve 


Nerve  to  outer  head  of  triceps 
Musculo-spiral  nerve 


Musculo-spiral  nerve 
(Ext.  cut.  br.) 


Fig.  35. — Musculo-spiral  nerve  on  posterior  surface  of  arm  ami  fore-arm. 
(After  Sappey.) 

It  then  divides  into  its  two  terminal  branches — 

1.  The  anterior  branch,  the  less  important,  exclusively  sensory,  follows 
the  direction  of  the  nerve,  proceeding  along  the  internal  edge  of  the  supi- 
nator longus  and  covered  by  it. 

At  the  lower  part  of  the  fore-arm,  it  passes  outwards  under  the  tendon 
of  the  supinator  longus,   passes  round    the  external   edge  of   the   radius, 


MUSCULO-SPIRAL    NERVE 


ici" 


becomes  subcutaneous  and  appears  at  the  dorsal  surface  of  the  wrist,  where 
it  divides  into  three  branches,  intended  for  the  sensory  in  nervation  of  the 
dorsal  surface  of  the  hand. 

2.  The  posterior  branch,  a  very  important  one,  passes  round  outside 
the   neck    of   the    radius,  traverses   the    supinator    brevis,   then    proceeds 


Musculo -spiral  nerve 
Br.  to  supinator  longus 


Sr.  to  extensor  carpi  radialis  longior 
Bifurc.  of  musculo-spiral  nerve 
Br.  to  exten.  carpi  radialis  brevior 


M 


usculo-spiral  nerve,  post.  br.  J 


Musculocutaneous  nerv< 


Radial  nerve 


Muscular  blanches 


Radial  nerve 


Radial  anil  musculo-cutaneous 

anastomosis 
Radial  nerve,  dig.  br. 


Fig.  36. — Musculo-spiral  nerve  or  posterior  surface  of  arm,  tore-arm  and  hand. 

(After  Sappey.) 

between  the  superficial  layer  and  the  deep  layer  of  the  posterior  muscles 

of  the  fore-arm,  supplying  all  of  them  with  motor  branches. 

Under  the  name  of  posterior  interosseous  nerve,  this  branch,  applied  to 
the  posterior  surface  of  the  interosseous  ligament,  extends  right  to  the  level 
of  the  wrist.  The  terminal  branches  arc  distributed  over  the  periosteum 
and  the  articulations  of  the  carpus  and  the  metacarpus  ;  we  shall  see  that 
their  trophic  role  is  a  particularly  important  one. 


102 


NERVE   WOUNDS 


Motor  Branches 


The  musculo-spiral  is  above  all  a  motor  nerve.  It  gives  off  in  turn 
the  following  motor  branches  : — 

i.  Below  the  axilla  at  the  posterior  surface  of  the  arm  :  the  nerve  to 
the  long  head  of  the  triceps ;  the  nerve  to  the  inner  head  ;  the  nerve  to 
the  outer  head,  which  extends  down  to  the  anconeus. 

2.  In  the  bicipital  furrow  :  the  nerve  to  the  supinator  longus ;  the 
nerve  to  the  extensor  carpi  radialis  longior. 

3.  In  passing  round  the  neck  of  the  radius,  the  posterior  branch 
supplies  :  the  nerve  to  the  exterior  carpi  radialis  brevior  and  the  branches 
to  the  supinator  brevis. 

4.  On  the  posterior  surface  of  the  arm,  this  same  branch  supplies  : 

the  nerve  to  the  ex- 
terior carpi  ulnaris  ;  the* 
nerves  to  the  extensor 
communis  digitorum 
and  to  the  extensor 
proprius  digiti  minimi, 
then  descending,  the 
nerves  to   the  extensor 

l  ossis  metacarpi  pollicis, 
to  the  extensor  longus 
pollicis  and  to  the  ex- 
tensor brevis  pollicis 
manus ;  the  nerve  to 
the  extensor  indicis. 

5.  Finally,  the  an- 
terior branch  sometimes 
supplies  the  thenar 
eminence  with  a  little 
branch  which  partici- 
pates in  the  innervation 
of  the  abductor  pollicis 

(the  median  supplies  the  principal  innervation  to  this  muscle). 

This  nerve  twig  has  no  great  importance  ;  all  the  same  it  explains  the 

very  slight  atrophy  of  the  abductor  sometimes  found   in   musculo-spiral 

paralysis. 


Posterior  ^IV^  M/Mf         Anterior 

aspect.  (yC"  aspect. 

Figs.  37  and  38. — Motor  distribution  of  the 

musculo-spiral. 


Sensory  Branches 


The  sensory  contribution  of  the  musculo-spiral  is  of  slight  importance. 
We  may  describe  its  three  branches — 

I.  Internal  cutaneous  branch  to  the   arm  which   is  given   oft  at   the 


MUSCULO-SPIRAL   NERVE 


103 


lower  part  of  the  axilla  and  goes  to  supply  the  postero-intcrnal  part  of  the 
arm  as  far  as  the  olecranon. 

2.  External  cutaneous  branch,  which  is  given  off  from  the  musculo- 
spinal just  when  it  passes  round  the  external  edge  of  the  humerus  and 
is  distributed  :  to  the  postero-external  surface  of  the  arm  ;  and  to  the 
posterior  surface  of  the  fore-arm,  in  the  form  of  a  narrow  band,  lying 
between    the    areas    of    the 

musculo-cutaneous   and    in- 
ternal cutaneous. 

3.  The  anterior  branch 
of  the  musculo-spiral  is 
predominantly  sensory.  It 
terminates  on  the  dorsal  sur- 
face of  the  wrist  in  three 
branches  which  supply  sen- 
sation to  the  external  part 
of  the  thenar  eminence,  to 
the  external  part  of  the 
dorsal  surface  of  the  hand, 
to  the  entire  dorsal  surface 
of  the  thumb,  to  the  dorsal 
surface  of  the  index  up  to 
the  second  phalanx,  to  half 
the  dorsal  surface  of  the 
middle  finger  up  to  the 
second  phalanx  (the  dorsal 
surface  of  the  last  phalanges  of  these  two  fingers  is  supplied  by  the  median). 


Figs.  39  and  40. — Sensory  distribution. 


Anastomotic  Branches 

The  musculo-spiral  nerve  presents  no  important  anastomosis  with  the 
other  nerves.  Its  sensory  fibres  alone  anastomose  with  the  sensory  fibres 
of  the  other  nerves  at  the  confines  of  its  cutaneous  region.  These  are 
terminal  anastomoses. 

We  meet,  however,  at  the  lower  third  of  the  fore-arm,  with  a  small 
twig  of  union  between  the  sensory  branch  of  the  musculo-spiral  and  the 
musculo-cutaneous. 


104 


NERVE   WOUNDS 


PHYSIOLOGY   OF   THE   MUSCULO  =  SPIRAL   NERVE 

MUSCULO-SPIRAL   PARALYSIS 

I. — Motor  Syndrome 

The  musculo-spiral  nerve  is  essentially  the  nerve  of  extension. 
i.  Paralysis  of  musculo-spiral  nerve  is  essentially  paralysis  of  extension. 
Extension  of  the  fore-arm  on  the  arm  by  the  triceps. 
Extension  of  the  hand  on  the  fore-arm   by  the  radial  extensors  on  the 
outer  side  and  by  the  extensor  carpi  ulnaris  on  the  inner  side. 


Fig.  41. — Attitude  in  musculo-spiral  paralysis. 

Extension  of  the  fingers  on  the  hand  by  the  extensor  communis  and 
by  the  extensors  of  the  thumb,  the  index  and  the  fifth  fingers. 

This  paralysis  results  in  a  special  deformity  :  the  fore-arm  half  flexed 
on  the  arm,  the  hand  drooping,  the  fingers  half  flexed  by  the  tonic  action 
of  the  flexors. 

But  paralysis  of  the    extensors  of  the   fingers    involves  only   the  first 


MUSCULO-SPIRAL    NERVE 


105 


phalanges;    if  we  artificially  raise  the  first   phalanges,   we  find  that  the 
patient  can  easily  extend  the  second  and  third  phalanges. 
For,     while    the     extensor 


Ext.  tend. 


Slip  to  first  phalanx 
I'.rt.  fib. 

Interossei 


Lumbricales 

Exp.  of  Aponeurosis 


Long  slip 


Fig. 


+2. 


-Tendons  of  the  common  extensor  ; 
connexions  (deep  aspect). 
We  see  that  the  exterior  tendon  sends  to  the  first 
phalanx  a  slip  of  insertion  which  limits  its  action 
to  this  phalanx  alone.  The  slips  intended  for  the 
second  and  third  phalanges  are  affected  by  the 
lumbricales  and  the  interossei. 


tendons  continue  right  to  the 
last  phalanx  of  the  fingers, 
they  really  act  along  their 
deep  surface,  on  the  head  of 
the  first  phalanx,  a  close  ad- 
hesion limiting  their  action  to 
the  extension  of  the  first 
phalanges  upon  the  metacarpus 
alone. 

It  is  the  interossei  that  ex- 
tend the  second  and  third 
phalanges  upon  the  first  by  the 
tendinous  slips  which  they 
send  to  the  extensor  tendons. 

Thus, orthopedic  appliances 
intended  to  correct  musculo- 
spiral  paralysis  have  no  need  to 
extend  more  than  the  first 
phalanx. 

2.  Musculo-spiral  paralysis 
is  accompanied  by  paralysis  of 
extension  of  the  thumb. 

3.  The  extensor  carpi  ulnaris  muscle,  which  is  an  extensor  of  the  hand 

on  the  fore-arm,  also  produces 
a  movement  of  adduction  of  the 
hand. 

Consequently,  abduction  is 
weakened,  though  it  remains 
possible  through  the  flexor  carpi 
ulnaris  (ulnar  nerve).  It  then 
occurs  along  with  flexion  of  the 
hand,  in  default  of  the  synergic 
antagonism  of  the  extensor  carpi 
ulnaris. 

4.  We  also  have  paralysis 
of  supination  (supinator  brevis). 

At  the  same  time  a  slight 
degree  of  supination  by  means 
of  the  biceps  persists,  but  this  is 
possible  only  if"  the  tore-arm  is 
flexed, 
longus.  —  Although     supplied    by     the 


Fie;.  43. — Extension  of  second  and  third 
phalanges  on  the  first,  by  the  action  of  the 
interossei  in  musculo-spiral  paralysis.  This 
patient,  suffering  from  musculo-spiral  para- 
lysis and  possessing  considerable  articular 
laxity  of  the  fingers,  succeeded,  in  spite  of  the 
droop  of  hand  and  fingers,  in  producing  with 
his  interossei  a  hyper-extension  oi  the  second 
and  third  phalanges. 


5.  Sign    of    the    supinator 


io6 


NERVE   WOUNDS 


musculo-spiral,  the  supinator  longus  is  not  an  extensor  ;  it  is  not  even  a 
supinator,  in  spite  of  its  name.  It  is  rather  a  flexor  of  the  fore-arm  on  the 
arm,  almost  as  powerful  as  the  biceps  ;  that  it  is  supplied  by  the  musculo- 
spiral  nerve  is  quite  an  anomaly,  since  it  really  belongs  to  an  altogether 
different  physiological  group,  that  of  the  flexors. 

It  contracts,  synergically  with  the  biceps,  in  every  flexion  of  the  fore- 
arm, standing  out  prominently. 

The  disappearance  of  this  synergic  contraction  of  the  supinator  longus 
is  one  of  the  best  signs  of  peripheral  musculo-spiral  paralysis.  Indeed, 
it  is  not  found  in  root  or  spinal  cord  paralyses  which  are  confined  to  the 
root  region  of  the  musculo-spiral  (essentially  the  seventh  cervical),  whilst 


Fig.  44. — Normal  subject.  Contraction 
of  the  supinator  longus  accompanying 
contraction  of  the  biceps. 


Fig.  45. — Musculo-spiral  paralysis.  The 
supinator  longus  does  not  contract 
synergically  with  the  biceps. 


leaving  untouched  the  upper  root  group  (deltoid,  biceps,  brachialis  anticus 
and  supinator  longus,  which  depend  mainly  on  the  fifth  and  sixth  cervicals). 

As  we  are  aware,  contraction  of  the  supinator  longus  is  retained  in 
saturnine  paralysis,  of  the  musculo-spiral  type. 

Any  musculo-spiral  paralysis  where  the  supinator  longus  is  untouched 
should  at  once  attract  attention.  If  this  dissociation  is  not  due  to  lesion  of 
the  nerve  below  the  branch  which  it  supplies  to  the  supinator  longus,  then 
we  are  dealing  with  pseudo-musculo-spiral  paralysis,  through  root  or  spinal 
cord  lesion,  polyneuritis,  or  hysterical  paralysis. 

6.  In  musculo-spiral  paralysis  we  note  a  considerable  diminution  of 
energy  in  flexing  the  fingers.  This,  however,  is  not  a  real  weakness,  but 
results    from  the  faulty  attitude  of  the  flexed    hand  ;  contraction  of  the 


MUSCULO-SPIRAL   NERVE 


107 


flexors  can  take  place  powerfully  only  if  the  antagonists  put  the  hand  in 
extension.  If  the  hand  is  artificially  raised,  the  fingers  will  regain  their 
full  power  of  flexion. 


II. — Sensory  Syndrome 

The  musculo-spiral  nerve  is  but  very  slightly  sensory,  its  region  is 
confined  to  the  posterior  part  of  the  arm,  a  tract  on  the  back  of  the  fore- 
arm and  a  part  of  the  dorsal  surface  of  hand  and  fingers. 

It  must  be  added  that  anaesthesia  of  the  internal  cutaneous  branch  is 
scarcely  noticeable  and  is  very  rare,  since  it  occurs  only  in  lesions  high  up 
in  the  axilla. 

The  external  cutaneous  branch  is  more  frequently  affected,  particularly 
in  fractures  of  the  humerus  ;  still,  we  can  just  discern  on  the  external 
surface  of  the  arm  and  behind  the  fore-arm  a  small  area  of  hypo-ajsthesia, 


Typical  distribution  Frequent  type.  Very  frequent 

of  anaesthesia.  tyPe- 


Anaesthesia  extend- 
ing beyond  the 
typical  region 
(very  rare). 

V\r..  46. — Types  of  anesthesia  from  lesions  of  the  musculo-spiral. 


so  restricted  is  its  sensory  role  and  so  great  the  overlapping  of  neighbouring 
nerves. 

Anaesthesia  in  musculo-spiral  paralysis  is  not  often  found  anywhere 
else  than  on  the  hand.  Seldom  does  it  reach  the  typical  distribution  of 
the  musculo-spiral,  far  more  seldom  does  it  go  beyond  it.  Most  frequently 
it  limits  itself  to  a  very  restricted  part  comprising  the  dorsal  region  of  the 
first  and  the  second  metacarpal. 

It  is  often  very  slight,  somctines  even  it  can  scarcely  be  seen  ;  in  any 
case,  it  is  exceptional  to  find  complete  anaesthesia  in  this  region  ;  at  most 
we  have  more  or  less  marked  hypo-aesthesia. 

In  this  same  region  is  found  formication,  brought  out  by  pressure  on 
the  nerve  ;  it  exists  even  in  cases  where  anaesthesia  is  scarcely  discernible. 
It  even  appears  at  times  in  lesions  of  the  posterior  branch,  showing  the 
presence  therein  of  sensory  fibres. 


io8 


NERVE   WOUNDS 


III. — Trophic  Syndrome 


In  musculo-spiral  paralyses  we  frequently  find  an  abnormal  projection 
of  the  bones  of  the  carpus,  forming  the  dorsal  swelling  of  the  carpus. 

Probably  this  is  due  to  simple  relaxation  of  the  carpal  ligaments  with 
slight  subluxation  of  the  os  magnum  and  of  the  semi-lunar,  rather  than  to 
genuine  trophic  disturbance.  In  some  cases,  and  especially  in  neuritis,  it 
seems  to  be  produced  by  an  actual  teno-synovitis  of  the  extensor  tendons. 
It  is  in  neuritic  forms  that  we  find  the  real  trophic  disturbances, 
attacking  the  integuments,  the  synovial  sheaths,  the  metacarpo-phalangeal 

and  digital  articulations. 

It  would  seem  extremely  probable 
that  this  trophic  role  is  due  partly  to 
the  posterior  branch  of  the  musculo- 
spiral,   for   it    is   found  even   in   cases 


of  the 


Fig.  48. — (Edema  of  the  hand  in  a  case 
of  musculo-spiral  paralysis  (section  of 
the  nerve). 


where  neuritic  irritation  acts  ex- 
clusively on  this  branch. 

The  nails  are  very  slightly 
affected  in  neuritis  of  the  mus- 
culo-spiral. We  know  that  its 
innervation  is  limited  to  the  first  phalanges.  Vascular  disturbances  are 
usually  very  slightly  marked  ;  most  frequently  they  are  lacking  ;  in  any 
case  they  never  possess  the  definite  character  of  the  vascular  disturbances 
of  the  median  and  the  ulnar. 

In  some  cases  of  musculo-spiral  paralysis  we  find  oedema  of  the  dorsal 
surface  of  the  hand.  This  is  rare,  though  it  is  met  with  both  in  nerve 
sections  and  in  nerve  irritation  ;  its  appearance  is  certainly  favoured  by 
the  drooping  attitude  of  the  hand. 


MUSCULO-SPIRAL    NERVE 


109 


TYPES   OF   MUSCULO-SPIRAL   PARALYSIS 

These  types  should  be  studied  : 

1.  According  to  the  seat  of  the  lesion  and   the   topographical   distri- 
bution of  the  paralysis  ; 

2.  According  to  the  clinical  type  produced  by  the  lesion  :   interruption, 
compression,  nerve  irritation  or  regeneration. 


TYPES   ACCORDING  TO   THE   SEAT   OF   LESION 
I. — Total  Paralysis  of  the  Musculo-spirai. 

This  is  produced   by  lesions  of  the  nerve    at   the  lower  part   of  the 
axilla  and  by  crutch  palsy. 

It  is  characterised  by  para- 
lysis of  the  triceps,  along  with 
abolition  of  the  olecranon  reflex, 
in  addition  to  all  the  other 
symptoms  of  musculo-spirai 
paralysis. 

We  note  the  complete  dis- 
appearance of  the  movements 
of  extension  of  the  fore-arm  on 
the  arm  ;  paralysis,  atrophy  and 
RD  of  the  triceps. 

After  all,  it  is  very  seldom 
found  in  its  pure  state,  for  the 
musculo-spirai  nerve  supplies 
its  first  tricipital  branches  im- 
mediately below  the  axilla.  It 
is  seen  more  frequently  in 
musculo-spirai  paralysis  associ- 
ated with  that  of  the  circumflex 
or  of  the  other  nerves  of  the 
arm  resulting  from  axillary 
lesions. 

Paralysis  of  the  triceps  easily 
passes  unperceived  unless  sought 
for  systematically  ;  indeed,  when 
at  rest,  it  is  not  indicated  by 
any  special  attitude.  It  is 
always  accompanied  by  exaggerated  passive  flexion  of  the  elbow. 

II. — Partial  Paralysis  of  the  Triceps 

The  triceps  is  supplied  by  three  different  branches  :   branches  to  the 
internal  head,  to  the  long  head,  and  to  the  external  head. 


Fig.  +9. — Paralysis  of  the  triceps.  Lesion  at 
the  base  of  the  axilla.  The  patient,  on  trying 
to  extend  the  fore -arm  on  the  arm,  succeeds 
only  in  raising  the  arm  outwards  and  hack- 
wards  by  contraction  of  the  deltoid  (circum- 
flex) ;  the  fore-arm  hangs  vertically. 


no 


NERVE   WOUNDS 


Lesions  between  these  branches  may  produce  partial  paralysis  of  the 
triceps. 

In  such  cases. we  have  to  deal  with  a  nerve  lesion  very  high  up,  at  the 
postero-internal  surface  of  the  arm.  We  always  find  paralysis  of  the 
outer  head  and  of  the  anconeus,  with  more  or  less  complete  integrity 
of  the  inner  head  and  the  long  head,  the  branches  of  which  originate  quite 
close  to  each  other,  one  or  two  centimetres  above  the  branch  to  the  outer 
head,  which  also  supplies  the  anconeus. 

It   is  often  difficult  to  detect  the 

S  existence  of  this  partial  paralysis  of  the 

triceps,  for  extension  of  the  fore-arm 
persists,  and  is  scarcely  diminished 
at    all.     Only    by    palpation    of    the 


Fig.  50.— Dissociated  paralysis  of  the 
triceps.  Integrity  of  the  long  head 
and  of  the  inner  head  ;  paralysis, 
atrophy  and  RD  of  the  outer  head. 
The  patient  is  making  an  effort  to 
extend  his  arm,  against  resistance. 


Fig.  51. — Musculo-spiral  paralysis  with 
dissociated  paralysis  of  the  triceps. 


contracting  muscle  can  we  recognise  the  flaccidity  and  atrophy  of  the  outer 
head.  Farad ic  examination  by  the  bi-polar  method  also  shows  the  per- 
sistence of  contraction  in  the  case  of  the  inner  head  and  the  long  head, 
their  disappearance  in  the  case  of  the  outer  head. 

The  olecranon  reflex  is  retained. 

The  external  cutaneous  branch  makes  its  appearance  below  the  tri- 
cipital  branches  ;  its  participation  is  indicated  by  a  faint  narrow  tract  of 
hypo-aesthesia  on  the  posterior  surface  of  the  fore-arm. 


III. MUSCULO-SPIRAL   PARALYSIS    ABOVE    THE    SUPINATOR    LoNGUS. 

This  is  the  classic  and  most  frequent  type  of  musculo-spiral  paralysis, 
that  produced  by  wounds  on  the  external  surface  of  the  arm,  simple 
compression  of  the  nerve  on  a  sharp  edge,  fractures  of  the  shaft  of  the 


MUSCULO-SPIRAL    NERVE 


1 1 1 


humerus  with  involvement  of  the  nerve  in  the  callus  or  in  the  surroundino; 
tissues.  Secondary  involvement  in  callus  of  a  musculo-spiral  nerve 
originally    intact   is    theoretically    possible  ;    it    must,    however,    be    quite 


Fig.  52. — Wounds  on  the  external  surface  of  the  arm  with  fracture  of  the  humerus. 
Typical  musculo-spiral. 

exceptional  ;  for  we  have  always  found   that  paralysis  occurs  immediately 
with  the  wound. 

Musculo-spiral  paralysis  is  characterised  at  this  level  by  inaction  of  the 
supinator  longus,  the  radial 
extensors,  the  extensor  carpi 
ulnaris,  and  the  extensors  of 
the  fingers,  causing  the  typical 
flexed  attitude  of  the  hand  and 
of  the  first  phalanx  of  the 
fingers. 

The  olecranon  reflex  is 
retained. 

The  triceps  is  of  course 
untouched,  as  is  the  anconeus. 

Although  this  small 
muscle  is  situated  below  the 
olecranon,  in  the  posterior 
compartment  of  the  fore-arm, 
it  is  no  more  than  a  pro- 
longation of  the  triceps  and  is 
supplied  by  the  branch  to  the 
outer  head. 

Its  integrity   is   indicated    by  no  special  attitude  or   movement,  but  it 
may  be  a  cause  of  error  in  electrical  examination.     Indeed,   if  we  try  to 


Posterior  aspect.       Anterior  aspect. 

FlGS.  53  and  54. — Musculo-spiral  paralysis  below 
the  triceps. 


112 


NERVE   WOUNDS 


obtain  faradic  excitability  of  the  posterior  muscles  of  the  fore-arm,  the 
anconeus,  excited  by  diffusion,  often  responds  by  slight  contractions  which 
may  be  taken  for  a  response  of  the  radial  extensors  or  of  the  extensors  of 
the  fingers. 

The  external  cutaneous  branch,  which  emerges  on  to  the  external 
surface  of  the  arm,  may  be  affected  by  the  lesion  or  remain  untouched,  as 
the  case  may  be.  Its  interruption,  moreover,  is  shown  only  by  a  slight 
and  faint  narrow  tract  of  hypo-aesthesia,  on  the  external  surface  of  the 
elbow  and  descending  on  to  the  posterior  surface  of  the  fore-arm. 

We  must  remember  that   if  the   musculo-spiral  nerve  is  found  to  be 

enclosed  in  callus,  it  is  sometimes 
rather  difficult  to  bring  about  the  sign 
of  formication  at  the  level  of  the  lesion. 
It  is  necessary  to  make  on  the  callus 
a  few  slight  taps,  capable  of  trans- 
mitting the  shock  to  the  enclosed 
nerve. 

Lesions  of  the  musculo-spiral  nerve 
by  involvement  in  callus  are  particu- 
larly likely  to  induce  symptoms  of 
nerve  irritation,  along  with  pains 
caused  by  pressure  on  nerve  and 
muscles,  trophic  disturbances  of  in- 
teguments and  digital  articulations, 
tendon  adhesions  limiting  the  passive 
flexion  of  the  fingers.  These  are  cases 
which  call  for  liberation  of  the  nerve, 
and  the  sooner  this  is  done,  the  more 

Fig.  55.— Paralysis    of    the    supinator    satisfactory  will  be  the  results  obtained. 
longus.     The  muscle  no  longer  con-  .~  ,  ,         .     , 

tracts  synergically  with  the  biceps.  Operations  on    the    musculo-spiral 

nerve  at  this  level,  sutures  and 
liberations  alike,  are  particularly  liable  to  be  followed  by  secondary  involve- 
ment in  the  callus  or  in  cicatricial  fibrous  tissue,  J?y  reason  of  the 
proximity  of  the  fractured  bone.  This  is  the  main  cause  of  lack  of 
success  after  operations.  Accordingly  it  is  usually  necessary,  more  than 
anywhere  else,  to  surround  the  nerve  with  a  muscular  or  fatty  envelope, 
and  at  an  early  stage  to  massage  and  mobilise  the  scar. 


IV. — Musculo  spiral  Paralysis  below  the  Supinator  Longus 

Lesions  at  the  lower  part  of  the  bicipital  furrow,  direct  traumatism  or 
fracture  of  the  epicondyle,  may  affect  the  musculo-spiral  immediately 
below  the  branch  to  the  supinator  longus. 

There  is  then  complete  paralysis  of  extension  of  hand  and  fingers,  but 


MUSCULO-SPIRAL   NERVE 


"3 


the   supinator   longus  is 
biceps. 

Several  times  we 
have  found  this  type 
in  neglected  fractures 
of  the  epicondyle  with 
a  fibrous  loop  enclosing 
the  nerve  at  the  level 
of  the  line  of  the  frac- 
ture. The  integrity  of 
the  supinator  longus 
might  have  made  one 
regard  it  as  a  functional 
paralysis. 

Still,  it  must  be 
remembered  that  the 
branches  to  the  supi- 
nator longus  and  to  the 
extensor  carpi  radialis 
longior  arise  near  each 
other  from  the  trunk  of 
the  nerve  itself,  whereas 
the  twig  to  the  extensor 
carpi  radialis  brevior  has 
its  origin  much  lower 
from  the  posterior  inter- 
osseous ;  accordingly 
there  will  often  be  ob- 
served weakening  of  the 
supinator  longus  accom- 
panied by  paralysis  of 
the  extensor  carpi  radi- 
alis longior.  More 
frequently  if  the  lesion 
is  in  the  vicinity  of  the 
joint  we  note  the  in- 
tegrity of  the  supinator 
longus,  simple  weaken- 
ing of  the  extensor 
carpi  radialis  longior 
and  paralysis  of  the 
extensor  carpi  radialis 
brevior  ;  electrical  ex- 
amination enables  us 
easily  to  dissociate  these 


untouched    and  contracts   synergically   with    the 


Fig.  56. — Origin  of  the 
branches  to  the  supinator 
longus  and  tothe  radial 
extensors. 


Fig.  57. — Integrity  of  the 
supinator  longus,  weak- 
ening of  the  extensor 
carpi  radialis  longior, 
paralysis  of  the  extensor 
carpi  radialis  brevior. 


wM             mL  V     fm 

■It  * 

Fig.   58. — Integrity  of  the  supinator  longus.      Atrophy 
and  paralysis  of  the  radial  extensors.      Wound  inflicted 
at     the]  middle   part   of   the   furrow    of  the   supinator 
1     longus. 

symptoms. 


ii4 


NERVE   WOUNDS 


V.  —  MUSCULOSPIRAL    PARALYSIS    BELOW    THE    R.ADIAL    EXTENSORS 

In  this  case,  the  lesion  is  of  the  posterior  branch  alone,  below  the  joint 
or  else  on  the  outer  surface  of  the  neck  of  the  radius  or  even  at  the 
posterior  surface  of  the  fore-arm. 


Fig.  60. — Wound  on  the  posterior  surface  of  the 
arm.     Integrity  of  the  radial  extensors.     Ex- 
tension of  hand  on  fore-arm  possible.     Para- 
lysis of  the  extensors  of  the  ringers. 
Fig.  59. — Integrity    of   the    radial 

extensors.     We  find    paralysed  : 

The  superficial  layer  of  muscles, 

extensor    carpi    ulnaris    and    ex- 
tensor     communis       digitorum, 

covering  the  deep  layer  made  up 

of  the    extensor  ossis  metacarpi 

pollicis,     the    extensors    of     the 

thumb  and  of  the  index. 

The  anterior  branch  is 
untouched  ;  consequently 

there  are  no  sensory  disturb- 
ances in  the  hand. 

Raising  of  the  hand  is 
possible  but  the  extensors  of 
the  fingers  and  the  extensor 
carpi  ulnaris  are  paralysed. 

If  there  is  considerable 
hypotonia  of  these  latter 
muscles,  we  may  see  the  con- 
traction of  the  radial  extensors 
raising  the  hand  by  giving 
it  a  deviatory  movement  out- 
wards ;  this  is  because  their  traction  takes  place  on  the  radial  side  of 
the  hand  and  must  normally  be  balanced  by  the  synergic  contraction 
of  the  extensor  carpi  ulnaris  on  the  inner  side  of  the  wrist. 


Fig.  61. — Contraction  of  the  radial  ex- 
tensors is  no  longer  balanced  by 
synergic  contraction  of  the  extensor 
carpi  ulnaris  ;  the  hand  deviates  to- 
wards the  radial  side. 


MUSCULO-SPIRAL   NERVE 


"5 


VI. — Dissociation  of  the  Extensor  Communis  Digitoru 


m 


Below  the  radial  extensors  and  the  supinator  brevis   a   lesion   of  the 
posterior   branch  of  the  musculo-spiral    may  affect   the   extensors  of  the 


ringers. 


The  extensor  communis,  however,  receives  its  supply  by  several  twigs 

corresponding    to     the    different     muscular 
fasciculi. 


Fig.  62. 


Fig.  63. — Dissociated  paralysis  of  the  extensor 
communis  digitorum.  Integrity  of  the  ex- 
tensor of  the  middle  finger. 


Fig.  64. — Dissociated  paralysis  of  the  extensor  communis  digitorum.     Integrity 
of  the  extensor  of  the  middle  linger. 


The  extensor  fasciculus  to  the  middle  finger  may  be  untouched  whilst 
the  underlying  fibres  are  affected,  and  we  find  extension  of  the  middle 
finger  persisting  when  the  other  extensors  are  paralysed. 


n6 


NERVE   WOUNDS 


VII. MUSCULO-SPIRAL    PARALYSIS   BELOW   THE    EXTENSOR    COMMUNIS 

DlGITORUM 

Below  the  branches  intended  for  the  extensor  communis  digitorum,  a 
twig  of  which  almost  always  terminates  at  the  extensor  of  the  little  finger, 

the  posterior  branch  of  the  musculo-spiral 
supplies  the  extensor  ossis  metacarpi  pollicis, 
the  long  and  short  extensors  of  the  thumb 
and  the  extensor  indicis. 


Fig.  65. 


Fig.  66. — Paralysis  of  the  extensors  of  the  thumb 
by  wound  at  the  middle  third  of  fore-arm. 


Consequently  we  may  have  isolated  paralysis  of  these  muscles  from  a 
lesion  of  the  musculo-spiral  at  the  middle  of  the  fore-arm. 

VIII. — Dissociated  Paralysis  of  the  Musculo-spiral 

Partial  fascicular  lesions  of  the  musculo-spiral  are  rare.  However,  we 
meet  with  certain  cases  which  occasion  dissociated 
paralysis. 

We  may  quote  two  types  of  these 
lesions — 

1.  The  musculo-spiral  nerve  crushed 
by  a  bony  fragment  of  the  humerus, 
level  with  the  furrow  of  the  biceps, 
seemed  to  present  symptoms  confined 
to  its  inner  part.  There  was  absolute 
paralysis  of  the  extensors  and  extensor 
carpi  ulnaris,  along  with  complete  RD  ; 
on  the  other  hand,  the  supinator  longus 
and  the  radial  extensors  had  retained 
some  voluntary  movements,  very  slight 
faradic  excitability  without  galvanic 
polar  inversion  and  also  without  slow 
contraction. 

The  modified  operation  performed 
on   this  nerve  was  followed   by  a  rapid  return  of  the  functions  in  the  case 


Fig.  67. — Dissociated  paralysis  ot  the 
musculo-spiral,  not  affecting  the 
supinator  longus  and  the  radial  ex- 
tensors. 


MUSCULO-SPIRAL    NERVE  117 

of  the  supinator  longus  and  the  radial  extensors,  whilst  paralysis  of  the 
extensors  and  of  the  extensor  carpi  ulnaris  persisted  three  months  after  the 
operation. 

2.  In  another  case  the  musculo-spiral  was  bruised  on  the  external 
surface  of  the  humerus,  the  contusion  apparently  involving  only  the 
posterior  and  external  part  of  the  nerve. 

There  was  found  to  he  complete  paralysis  of  the  supinator  longus  and 
the  radial  extensors  with  considerable  atrophy  and  a  complete  reaction  of 
degeneration,  whilst  the  voluntary  mobility  of  the  extensors  of  the  fingers 
was  fully  retained  along  with  normal  electrical  reactions. 


Fig.  68. — Contusion  on  the  external  surface  of  the  arm  ;  dissociated  paralysis  ot  the 
musculo-spiral,  integrity  of  the  extensors  ;  paralysis  of  the  radial  extensors  and  ot  the 
supinator  longus.  No  operation  ;  persistence  of  this  paralysis  three  months  atter 
the  first  examination.  The  patient  is  photographed  just  as  he  is  extending  his  fingers, 
usually  flexed  in  an  attitude  of  repose. 

Thus  there  would  appear  to  exist  in  the  musculo-spiral,  as  in  all  the 
other  nerves,  a  fascicular  topography.  It  is  somewhat  difficult  to  deter- 
mine it  precisely,  mainly  perhaps  on  account  of  torsion  of  the  nerve,  which 
at  each  stage  modifies  the  position  of  the  different  fasciculi. 

But  still  it  must  be  admitted  that  we  find  :  on  the  outer  side,  and 
from  front  to  back,  the  anterior  cutaneous  branch,  the  supinator  longus, 
the  radial  extensors  ;  on  the  inner  side,  from  front  to  back,  the  extensor 
carpi  ulnaris  and  the  muscles  of  the  thumb,  the  extensor  communis,  the 
supinator  brevis.     (J.  and  A.  Dejerine  and  Mouzon.) 

According  to  MM.  Pierre  Marie  and  Meige,  we  find  the  extensors  of 
the  wrist  on  the  inner  side,  the  extensores  digitorum  within  and  behind, 
the  supinators  on  the  outer  side. 


n8 


NERVE   WOUNDS 


FORMS  OF    MUSCULO-SPIRAL    PARALYSIS  ACCORDING  TO  THE 
NATURE   OF   THE   LESION 

I. — Syndrome  of  Compression 

This  is  characterised,  especially  in   musculo-spiral  paralysis,  by  partial 
preservation  of  muscular  tone  for  a  long  period. 


Fig.  69. — Simple  compression  of  the  musculo-spiral  ;  paralysis  "a  frigore." 
Persistence  of  muscular  tone. 

The  droop  of  the  hand  is  slight,  very  little  if  at  all  more  pronounced 
than  in  the  position  of  simple  muscular  repose. 

If  we  press  on  the  hand,  we  may  intensify  the  flexion  ;    if  we  cease 


Fig.  70. — Compression  of  the  musculo-spiral  in  callus.     Persistence  ot 
muscular  tone. 

pressing,  the  hand  is  seen  to  resume  its  original  attitude,  as  a  result  of  the 
muscular  elasticity. 

In  the  long  run,  however,  we  find   hypotonia   becoming  pronounced, 
and  the  hand  assuming  the  attitude  of  complete  interruption. 


MUSCULO-SPIRAL    NERVE 


119 


With  the  conservation  of  tone  is  associated  the  relative  absence  of 
muscular  atrophy,  the  incomplete  character  of  the  RD,  and  the  persistence 
of  a  slight  degree  of  muscular  sensation. 

It  is  in  slight  cases  of  compression  of  the  musculo-spiral  that  we  may 
sometimes  find  by  electrical  examination  the  paradoxical  preservation  of 
faradic  contractility  of  the  nerve  and  muscles  below  the  lesion. 

The  prognosis  of  these  forms  is  particularly  benign  ;  the  cure  comes 
about  spontaneously  in  a  few  weeks,  being  accelerated  by  electrical  treat- 
ment. 

II. — Syndrome  of  Interruption 

In  complete  interruptions,  on  the  other  hand,  we  find  that  muscular 
atony  rapidly  appears  and  becomes  more  marked. 


Fie.  71. — Complete  section  of  the  musculo-spiral  (a  separation  of  3  cm.  between  the 
two  segments)  at  the  upper  part  of  the  furrow  of  the  biceps.  Hypotonia  very 
pronounced. 


FlG.  72.— Complete  interruption  of  the  musculo-spiral,  by  compression  by  callus 
in  a  fracture  of  the  humerus.     Hypotonia  very  pronounced. 


120 


NERVE   WOUNDS 


The  droop  of  the  hand  at  the  wrist  is  complete  :  pressure  on  the  back 
of  the  hand  does  not  intensify  this  attitude  nor  is  it  followed  by  an  elastic 
return  to  the  normal  attitude. 


Fig.  73. — Complete  interruption  of  the  musculo-spiral,  nine  months  previously. 
Crushing  of  the  nerve  and  involvement  in  callus  of  fractured  humerus.  Extreme 
hypotonia. 

On  the  other  hand,  atrophy  of  the  muscle  and  RD   rapidly  appear  ; 
muscular  analgesia  is  complete. 


Fig.  74. — Section  of  the  musculo-spiral  on  the  outer  surface  of  the  humerus.     Complete 
hypotonia.     (In  this  case  there  also  exists  a  very  slight  ulnar  griffe.) 

No  great  reliance  must  be  placed  on  the  fixity  of  anaesthesia,  for  it  is 


MUSCULO-SPIRAL    NERVK  121 

well  known  that  amesthesia  may  be  extremely  reduced  in  musculo- 
spiral  paralysis. 

Still,  in  spite  of  the  slight  importance  of  sensory  disturbances,  on 
pressing  the  nerve  at  the  level  of  the  lesion,  it  is  always  found  that 
formication  manifests  itself  on  the  dorsal  surface  of  the  thumb  and  of  the 
second  metacarpal. 

Muscular  hypotonia,  after  some  months  of  complete  interruption,  may 
reach  an  extreme  degree  :  the  articular  ligaments  relax,  the  tendons 
lengthen  ;  flexion  of  the  hand  reaches  an  angle  of  90  and  even  more  ;  the 
hand  is  no  longer  simply  flexed,  it  is  hanging  loose  ;  the  flexors  have 
ended  by  losing  all  action  and  now  exhibit  functional  inertia  from 
disuse,  which  in  certain  cases  might  make  one  think  they  were  paralysed, 
had  they  not  retained  their  normal  electrical  reactions. 

III. — Syndrome  of  Nerve  Irritation 

Nerve  irritation  in  the  musculo-spiral  nerve  is  very  frequent,  and 
important  to  investigate,  for  it  involves  a  somewhat  serious  prognosis  by 
reason  of  the    tendon  adhesions  and  articular  limitations  which    it   pro- 


Fig.  75. — Nerve  irritation  of  the  musculo-spiral.  Droop  or  the  hand  less  pronounced. 
Extension  of  the  fingers  by  contraction  of  the  extensors  and  adhesion  of  their  tendons 
to  the  dorsal  surface  of  the  hand. 

duces.     Still,  it  is  often  disregarded,  as  it   is  unaccompanied  by  the  acute 
intolerable  pains  which  characterise  neuritis  in  other  nerves. 

The  musculo-spiral,  we  must  repeat,  is  but  slightly  sensory  ;  its  irri- 
tation consequently  is  not  expressed  by  the  painful  syndrome  of  neuritis 
in  the  ulnar  and  especially  the  median.  The  nerve  is  at  most  slightly 
sensitive  ;  the  point  where  the  posterior  branch  crosses  the  neck  of  the 
radius  is  found  to  be  particularly  painful  to  pressure  ;  the  antibrachial 
muscular  masses  are  somewhat  tender  if  pressed  ;  occasionally  we  find 
slight  hyper-aesthesia  of  its  cutaneous  region. 


122 


NERVE   WOUNDS 


But  whilst  sensory  disturbances  are  reduced  to  these  scattered  mani- 
festations, trophic  disturbances,  on  the  other  hand,  are  very  important. 


PiG-  76. — Nerve  irritation.  Tendency  to  hyper-extension  of  the  first  phalanges.  Con- 
siderable limitation  of  flexion,  active  or  passive.  Acute  pains  caused  by  attempts  at 
flexion. 


The  attitude  is  different  ;  the  droop  of  the  hand   is  less  pronounced, 
flexion  of  the  wrist  is  diminished  by  fibrous  adhesion  of  the  tendons  and 

contraction  of  the  extensor  muscles 
which  are  sometimes  felt  to  be  indu- 
rated, infiltrated,  and  painful  under 
pressure.  No  longer  have  we  the 
half-flexed  fingers  usual  in  musculo- 
spiral  paralysis  ;  they  remain  extended 
on  the  hand,  held  in  place  by  their 
contracted  tendons. 

Adhesion  of  the  extensor  tendons 
to  the  dorsal  surface  of  the  carpus  and 
fingers  is  such  that  it  considerably 
limits  or  even  makes  impossible  flexion 
of  the  fingers,  whether  active  or 
passive.  Even  if  pressure  be  exercised 
on  the  dorsal  surface  of  the  hand,  the 
attitude  of  the  rigid  fingers  may  be  seen 
intensified  in  hyper-extension. 

The  aspect    of  the    hand    is  cha- 
racteristic :    fibrous    infiltration  of  the 
dermis,  desquamation  of  the  epidermis 
in  fine  scales,  adhesion  of  the  skin  on  the  dorsal  surface  of  the  fingers  and 
particularly  at  the  level   of  the   first  digital   articulations,  disappearance  of 


Fig.  77. — Nerve  irritation.  Sponta- 
neous hyper-extension  of  the  fingers. 
Impossibility  of  flexion. 


MUSCULO-SPIRAL    NERVE 


123 


the  cutaneous  creases,  swelling  of  the  digital  articulations  or  rather  tapering 
of  the  fingersare  very  pronounced , 
they  sometimes  recall  the  appear- 
ance of  chronic  blennorrhagic 
rheumatism  or  of  certain  types 
of  arthritis  deformans.  The 
nails,  however,  are  simply  curved, 
far  less  affected  than  in  neuritis 
of  the  median  and  the  ulnar. 
For  it  is  known  that  dorsal 
innervation  of  the  last  phalanges 
is  mainly  supplied  by  the  palmar 
nerves. 

All  these  disturbances  not 
only  exist  on  the  first  fingers,  in 
the  cutaneous  region  of  the 
musculo-spiral,  they  extend  to 
the  entire  hand  and  fingers,  being 
pronounced  in  the  case  of  thumb, 
index  and  middle  fingers.  This 
inclines  one  to  think  that  they  Fig.  78. — Nerve  irritation.  Hyper-extension 
are   due   mainly   to    irritation    of        °f  th,e   fingers   caused   by   pressure  on    the 

.  ,  dorsal  surface  or  the  hand, 

the     posterior      branch     or     the 

musculo-spiral,  which,  as  we  know,  is  distributed  over  the  five  interosseous 


N 


Fig.  79.— Nerve  irritation  of  the  musculo-spiral.  (In  this  case  the  wound  is  located  at 
the  middle  third  of  the  fore-arm.)  No  musculo-spiral  paralysis,  except  slighl  weaken- 
ing of  the  extensors  of  thumb  and  index  ringer.  Severe  irritative  lesions  in  the 
hand.     Smoothness  and    fibrous   infiltration  of  the  skin,  rigidity  of    the   fingers  ami 

tendon  adhesions.      It  is  impossible  to  flex  the  fingers. 


I24 


NERVE   WOUNDS 


spaces.  Moreover,  one  may  see  all  the  trophic  disturbances  of  neuritis  of 
the  musculo-spiral  in  isolated  wounds  of  the  posterior  branch  of  the 
musculo-spiral,  in  the  fore-arm,  even  at  its  lower  part  or  almost  at  the 
wrist,  below  all  its  motor  branches. 

Neuritis  of  the  musculo-spiral  is  particularly  serious  on  account  of  its 
consequences  ;  for,  even  after  healing,  when  the  muscles  have  lost  their 
fibrous  consistence  and  regained  their  functions,  we  find  the  persistence 


Fig.  80. — Neuritis  of  the  musculo-spiral,  healed  three  months  previously.  All  the 
movements  have  reappeared,  atrophy  has  lessened,  the  pains  have  disappeared.  After 
three  months  of  massage  and  mobilisation,  however,  flexion  of  the  ringers  is  still 
extremely  limited,  however  energetically  it  is  attempted  ;  the  extensor  tendons  are 
united  to  the  dorsal  surface  of  the  metacarpals  and  the  digital  articulations.  Mobilisa- 
tion of  the  fingers  is  extremely  painful. 

of  flexion  of  the  hand  and  fingers  resulting  from  adhesion  of  the  tendons 
united  to  their  synovial  sheaths  and  from  the  fibrous  infiltration  of  the  peri- 
articular tissues  ;  these  fibrous  sequela?,  refractory  to  mobilisation  and 
massage,  continue  for  months  and  years  ;  they  may  constitute  actual 
infirmity,  accompanied  by  almost  total  incapacity  of  the  hand. 


Syndrome  of  Regeneration 

Regeneration  of  the  muscles  takes  place  from  above  downwards, 
following  the  path  of  the  axis-cylinders,  unless  a  partial  obstacle  to  the 
regeneration  of  a  nerve  fasciculus  create  a  dissociated  paralysis. 

Then  we  find  the  muscles  successively  resuming  their  movements  ; 
supinator  longus,  radial  and  other  extensors. 

But  when  paralysis  has  lasted  some  time,  prolonged  flexion  of  the 
hand  produces  an  actual  lengthening  of  muscles  and  tendons  This  lengthen- 
ing of  muscles  lasts  for  a  considerable  time,  and  we  find  that  patients,  who 
have    recovered    the    movements  of   their   radial  and   other  extensors  are 


MUSCULO-SPIRAL   NERVE 


125 


temporarily  incapable  of  executing  simultaneously  the  movements  of  these 
two  muscular  groups. 

"When  I  wish  to  raise  my  hand,"  says  the  patient,  "I  cannot  raise 
my  fingers.  When  I  wish  to  stretch  out  my  fingers,  I  am  compelled  to 
bend  my  hand  !  "     And,  as  a  matter  of  fact,  the  extensor  tendons,  when 


Figs.  81  and  82. — Impossibility  of  simultaneous  extension  of  hand  and  fingers.  Two 
attitudes  of  the  same  patient  after  regeneration  of  the  musculo-spiral  (divided  at  tin- 
external  surface  of  the  arm,  sutured  on  the  10th  of  June,  1 9 1 5.  Photographed  20th 
December,  1915). 

lengthened,  are  powerless,  unless  the  patient  stretches  them  by  previous 
flexion  of  the  wrist. 

The  extensors  of  thumb  and  index  are,  as  a  rule,  the  last  to  resume 
their  functions. 

To  assure  oneself  of  the  complete  cure  of  musculo-spiral  paralysis,  one 
may  request  the  patient  to  extend  his  hand  in  the  position  adopted  when 
taking  an  oath  or  ask  him  to  stand  at  attention,  his   little  finger  touching 


126  NERVE    WOUNDS 

the  outer  seam  of  the  trouser  leg  ;  any  defect  of  the  musculo-spiral  is 
indicated  by  the  impossibility  of  effecting  the  complete  supination  thus 
called  for.     (Pities  and  Testut.) 


DIAGNOSIS   OF   MUSCULO=SPIRAL   PARALYSIS 

Three  main  causes  of  error  must  be  mentioned. 

i.  Destruction  of  the  muscles  of  the  fore-arm,  a  frequent  occurrence. 
In  these  cases,  which  are  usually  somewhat  complex,  loss  of  muscular 
substance,  cicatricial  adhesions  and  a  certain  degree  of  functional  inertia 
of  the  traumatised  muscles  are  associated  most  frequently  with  the  nerve 
lesions  in  causing  loss  of  motion. 

Speaking  generally,  there  takes  place  secondarily  a  cicatricial  contraction 


Fig.  83. —  Large  wound  on  the  posterior  surface  of  the  fore-arm.  Almost  complete 
destruction  of  the  radial  extensors  and  of  the  extensor  communis.  Cicatricial  contrac- 
tion of  the  radial  extensors  causing  immobilisation  ot  the  hand  in  a  state  of  extension. 
Droop  of  fingers  is  complete,  although  what  remains  of  the  muscle  has  retained  its 
faradic  excitability. 

of  the  wounded  muscles  which  does  away  with  the  paralytic  attitude 
and  renders  the  extended  hand  motionless. 

2.  Hypotonia  and  lengthening  of  the  radial  extensors  and  other  muscles 
by  traumatism  or  prolonged  mal-position,  or  again,  traumatic  lengthening 
of  their  tendons. 

Violent  bruises  and  injuries  of  the  antibrachial  muscles,  or  even  simply 
— a  still  more  curious  thing — the  prolonged  attitude  of  the  hand  in  a  state 
of  flexion,  often  induce  so  pronounced  a  muscular  hypotonia  of  the  radial 
extensors  and  other  muscles  that  the  result  is  very  similiar  to  musculo- 
spiral  paralysis.  But,  though  the  patient  appears  in  the  attitude  character- 
istic of  this  paralysis,  though  he  experiences  great  difficulty  in  raising  his 
hand  and  especially  in  keeping  it  extended,  still,  these  movements  are  possi- 
ble ;  they  may  be  called  forth  by  the  will,  or,  if  need  be,  by  faradisation. 


MUSCULO-SPIRAL   NERVE 


127 


This  muscular  lengthening  slowly  improves  with  the  use  of  faradisa- 
tion, exercise  and  massage  ;  in  obstinate  cases,  shortening  or  plication  of 
the  tendons  of  the  radial  extensors  may  be  practised.      (Delorme.) 


■    ~'r3?TJF: 


Figs.  84  and  85. — Wound  on  the  antero-internal  surface  of  the  arm.  No  paralysis  at 
all,  but  a  comminuted  fracture  of  the  humerus.  Prolonged  immobilisation.  Sling 
•Tvorn  for  13  months'.  .  .  .  Attitude  of  musculo-spiral  paralysis  with  extreme 
hypotonia  of  the  muscles.  Voluntary  motion,  however,  is  retained  ;  at  the  cost  of 
Considerable  effort  the  patient  is  able  to  raise  his  hand. 

Simple  contusions  also,  crushing  or  section  of  the  tendons  of  the  radial 
extensors,  whilst  tending  to  lengthen  them,  bring  about  a  similar  attitude 
and  the  same  difficulty  in  extension  of  the  hand. 


Fig.  86. — Wound  on  dorsal  surface  of  the  wrist  with  contusion  and  lengthening 
of  the  tendons  of  the  radial  extensors, 

3.  Hysterical  paralysis  of  the  hand  almost  always  presents   itself  under 
the  guise  of  musculo-spiraljparalysis. 


i28  NERVE   WOUNDS 

It  is  soon  seen,  however,  that  flexion  is  impossible,  just  as  extension  is. 
The  persistence  of  electrical  reactions,  segmentary  anaesthesia,  the  mental 
state  of  the  subject,  the  disproportion  between  wound  and  paralysis,  even 
absence  of  any  wound,  readily  enable  a  diagnosis  to  be  made. 

Still,  we  must  not  trust  to  electrical  examination  alone,  for  it  often 
happens  that,  in  musculo-spiral  paralysis  a  frigore,  as  a  result  of  com- 
pression during  sleep,  the  muscles  have  retained  their  normal  electrical 
reactions.  This  is  the  paradoxical  phenomenon  described  by  Erb.  It 
would  appear  that  nerve- compression,  sufficient  to  interrupt  the  voluntary 
nerve  impulse,  is  not  sufficiently  pronounced  to  cause  degeneration  of 
the  axis-cylinders.     The    latter   continue   normal  below  the  lesion  ;  the 


Fig.  87. — Crushing  of  the  radial  tendons  and  extensors  at  the  level  of  the  wrist  caused 
by  the  kick  of  a  horse.  Lengthening  of  the  tendons.  Attitude  of  musculo-spiral 
paralysis  has  persisted  for  6  years.  Voluntary  extension  of  hand  and  fingers  is  possible, 
though  at  the  cost  of  considerable  effort. 

nerve  and  muscles  below  the  lesion  have  retained  their  normal  electrical 
reactions  ;  nevertheless,  voluntary  paralysis  is  complete,  the  supinator 
longus  does  not  contract  with  the  biceps.  Finally,  electrical  stimulation 
of  the  nerve  at  the  upper  part  of  the  arm  causes  contraction  of  the  triceps 
but  produces  no  movement  whatsoever  of  the  antibrachial  muscles.  Thus, 
a  slight  compression  arrests  the  nerve  impulse  as  does  electrical  excitation, 
without  interrupting  the  trophic  action  of  the  nerve  cells  in  the  cord  on 
the  peripheral  axis-cylinders. 

This  is  important ;  ignorance  of  the  fact  would  expose  one  to  the  risk 
of  regarding  as  functional,  musculo-spiral  paralysis  resulting  from  com- 
pression, although  the  rapid  cure  of  these  slight  compressions  within 
a  few  weeks,  their  motor  character  and  the  sign  of  the  supinator  longus 
enable  them  to  be  easily  recognised. 


MUSCULO-SPIRAL   NERVE 


129 


TREATMENT. 

Apart  from  the  therapeutic  ideas  we  may  hold   common  to  all  nerve 
lesions,  in  the  case   of  musculo-spiral    paralysis,  we   must   insist  on    the 


Figs.  88  and  89. — Slight  wound  at  the  level  of  the  wrist.  Hysterical  paralysis  of  t hc- 
hand  of  12  months'  standing.  Attitude  of  musculo-spiral  paralysis.  Persistence  ot 
electrical  reactions. 

necessity  of  keeping  the  hand  in  an  extended  position,  even  hyper-extended, 
during  the  whole  period  of  the  paralysis. 

We   apply  either    a    plaster  splint,  an  armlet  or  leather   glove,  or   a 
spring  appliance  of  which  many  models  are  to  be  obtained. 

9 


130 


NERVE    WOUNDS 


The  application  of  rubber  bands  or  springs  to  the  first  phalanges  will 
permit  of  extension  of  the  fingers. 

To  obtain  elevation  of  the  first  phalanx  is  sufficient,  since  the  last  two 
are  extended  by  the  interossei. 


Fig.  90. — Hinged  support  allowing  the  hand  to  be  maintained  in  the  desired  position  by 
altering  the  angle  with  the  fore-arm.  Aluminium  splint  fixed  by  broad  leather  armlet 
to  the  fore-arm.     (Apparatus  of  Pierre  Marie  and  Meige.) 


Fig.  91. — Spring  appliances  intended  to  correct  incapacity  of  the  extensor  muscles  of  the 
hand  and  fingers  in  musculo-spiral  paralysis.  The  apparatus  is  fastened  to  the  fore-arm 
by  a  long  leather  armlet.  It  permits  of  flexion  of  fingers  and  hand  (which  are  pre- 
served), it  also  permits  of  objects  being  grasped.  A  leather  ring  fixed  to  a  spring 
keeps  the  thumb  apart.     (Apparatus  of  Pierre  Marie  and  Meige.) 


Fig.  92. — Lemoing's  glove  (imitated  from  Sollier's  apparatus).      A  steel  plate  forming 
a  spring  is  applied   to  the  palmar  surface  which  it  elevates  ;  small  springs  produce 


extension  of  the  fingers  by  traction  on  leather  rings, 
are  able  to  write  and  to  roll  cigarettes. 


With  this  apparatus,' patients 


All  these  appliances  not  only  enable  a  patient  to  use  his  hand  and 
fingers  and  thus  avoid  weakening  of  the  flexors  through  inaction,  they  also 
do  away  with  muscular  lengthening  from  the  prolonged  flexed  position. 


MUSCULO-SPIRAL   NERVE 


'31 


Fig.  93. — Lcri  and  Dagnan-Bouveret  apparatus  tor  musculo-spiral  paralysis. 


Fig.  94. — Apparatus  of  Mauchet  and  Anceau. 


CHAPTER    VII 


ULNAR  NERVE 


ANATOMY 

The  ulnar  nerve  is  supplied  from  the  lower  roots  of  the  brachial  plexus 
(eighth  cervical  root  and  first  dorsal). 

It  is  given  off  from  the  inner  cord  of  the  plexus  along  with  the  inner 
head  of  the  median,  a  little  beyond  the  internal  cutaneous  and  the  lesser 
internal  cutaneous. 

It  traverses  the  axilla  and  descends  to  the  inner  side  of  the  arm,  behind 

the    median    nerve    and    the    brachial 
artery.     It  is  closely  united  with  them 
as  far  as  the  lower  third  of  the  arm ; 
this    is    why   we    so    frequently    find 
associated,  at  this  level,  lesions  of  the 
median,    the    ulnar    and     the    brachial 
artery.     The  internal  cutaneous,  which 
is    more   superficial,   descends    internal 
to    and    in    front  of 
the     neuro-vascular 
bundle. 

Starting  at  the 
lower  third  of  the 
arm,  the  ulnar  sepa- 
rates from  theneuro- 
vascular  bundle,  per- 
forates the  internal 
intermuscular  sep- 
tum, passes  into  the 

posterior      compart- 
Figs.  95  and  96.— Course  of  ulnar  and  median  (diagrammatic).     ment  Qf  tfoe  arm  amj 

then  into  the  epitrochlear  groove. 

In  the  fore-arm  it  passes  round  the  inner  side  of  the  elbow  to  reach 
the  anterior  region  of  the  fore-arm.  It  passes  under  the  flexor  carpi 
ulnaris  and  then  descends  along  its  external  edge  resting  on  the  flexor 
profundus,  and  covered  by  the  epitrochlear  muscles  and  the  superficial 
flexor. 


ULNAR    NERVE 


*33 


It  thus  descends  along  the  flexor  carpi  ulnaris  right  to  the  pisiform  ; 
it  is  here  confined  in  the  carpal  canal,  of  which  it  occupies  the  inmost 
part. 

At  this  level  it  gives  off  its  two  terminal  branches — 

Superficial  palmar  branch  (sensory). 

Deep  palmar  branch  (motor). 

Motor  Branches 

The  ulnar  supplies  no  branch  whatsoever  to  the  arm. 
To  the  fore-arm  it  supplies — 


Br.  to  brach.  amicus 


Anastom.  with  median  and 
musculo-cutan. 


Mus.  cut.  N. 

Mus.  spir.  N. 

Mus.-spir.  (ext.  br."! 


us.  cut.  N. 
N.  to  coraco-brach. 
Int.  cut. 

Br.  to  biceps. 


Median  N. 


Ulnar  N. 


Iut.  cut.  (ant.  br.) 


Anterior  aspect. 
Fir;.  97. — Deep  nerves  of  the  arm  (after  Sappey). 

1.  The  nerve  twig  to  the  flexor  carpi  ulnaris. 

2.  Two  motor  branches  for  the   two   internal    fasciculi   of  the  flexor 
profundus  digitorum. 

To  the  hand.     The  deep  palmar  branch  alone  is  motor. 
It  supplies — 

1.  Three  nerve  twigs  destined  for  the  three  muscles  of  the  hypothenar 
eminence  ; 

2.  The  nerves  destined  for  all  the  intcrossei,  both  palmar  and  dorsal  ; 


J34 


NERVE   WOUNDS 


its  internal  branch  supplies  the  digital  collateral  twig  to  the  inner  side  of 
the  little  finger.  Its  external  branch  supplies  digital  collateral  twigs  to  the 
contiguous  sides  of  the  little  and  ring  fingers. 


Supinator  longus. 

Muse. -spiral  N.  (post,  br.) 
Muse. -spiral  N. 

Ext.  carp,  radial,  longior 
Radial  N. 

Tendon  superfic.  flexor 
Ext.  carp,  radial,  brevior 

Radial  artery 

Median  N. 


Supinator  longus 
Pronat.  cpuadrat. 


Flexor  carpi  radia 
Opponens 


-Median  N. 


Pronator  radii  teres 
Brachial  artery 


exor  carpi  radialis 
Flexor  carpi  ulnaris 


Ulnar  N. 
Ulnar  artery 


Inteross.  N. 
-Ulnar  N.  (dors,  br.) 

Median  N.  palmar,  cut.  br. 

Ulnar  N.  (deep  br.) 
Ulnar  N.  (sup.  br.) 
Opponens. 


Anterior  aspect. 
Fig.  98. — Deep  nerves  of  fore-arm  ami  hand  (after  Hirschfeld). 

3.  The  nerves  destined  for  the  adductors  of  the  thumb  and  for.  the 
inner  head  of  the  flexor  brcvis  pollicis. 


ULNAR    NERVE 


135 


Sensory  Branches 

In  the  hand,  the  superficial  palmar  branch  is  exclusively  sensory. 

Its  internal  branch  supplies  the  digital  collateral  twig  to  the  inner  side 
of  the  little  finger,  its  external  branch  supplies  digital  collateral  twigs  to 
the  contiguous  sides  of  the  little  and  ring  fingers. 

In  the  fore-arm  the  ulnar  supplies — 


Musculo-spiral  N.  ) 
(Ext.  branch)  j 


Musculo-cutaneous  N. 
(post,  branch) 


Radial  nerve 


Musculo-spiral  N.  ) 
(collat.  branch)  ) 


Inter,  cut.  (post,  brach.) 


Inter,  cut.  (ant.  brach.) 


Ulnar  N.  (dorsal 
iranch) 


Posterior  view. 

Fig.  99. — Superficial  nerves  of  fore-arm  and  hand '(after  Sappey). 

1.  The  branch  to  the  ulnar  artery  which  begins  at  the  middle  third  of 
the  fore-arm,  follows  the  ulnar  artery,  becomes  subcutaneous  at  the  level 
of  the  wrist  and  goes  on  to  supply  the  skin  of  the  inner  side  of  the  wrist 
and  of  the  hypothenar  region  ; 

2.  The  dorsal  cutaneous  branch  of  the  hand  begins  at  the  middle  third 
of  the  fore-arm,  passes  over  the  inner  border  of  the  ulna,  and  becomes 
dorsal  ;  it  distributes  itself  over  the  skin  of  the  dorsal  region  of  wrist  and 
hand.     On  its  inner  side  it  supplies — 


136 


NERVE   WOUNDS 


The  dorsal  digital  collateral  of  the  little  finger  ; 

The  dorsal  digital  collaterals  of  the  little  finger  and  the  contiguous 
margin  of  the  ring-finger  ; 

The  digital  collateral  of  the  outer  side  of  the  ring-finger  and  the  con- 
tiguous margin  of  the  middle  finger. 

It  must  be  observed  that  the  dorsal  collateral  nerves,  supplied  by  the 
ulnar,  become  spent,  as  do  those  supplied  by  the  musculo-spiral,  towards 
the  extremity  of  the  first  phalanx.  It  is  the  palmar  collaterals  which 
supply  the  dorsal  surface  of  the  last  two  phalanges. 

Still,  an  exception  should  be  made  for  the  little  finger,  supplied  as  far 
as  its  extremity  by  the  dorsal  collaterals  of  the  ulnar,  just  as  the  thumb  is 
supplied  right  on  to  its  extremity  by  the  dorsal  collaterals  of  the  radial. 

Vasomotor,  Trophic  and  Articular  Branches 

The  ulnar  supplies  twigs  to  the  articulation  of  the  elbow,  to  the  ulnar 
artery,  to  the  articulations  of  the  carpus,  to  the  palmar  aponeurosis  and  to 
the  interosseous  spaces. 

We  shall  find  that  the  trophic  role  of  this  nerve  is  important. 

PHYSIOLOGY  OF  THE  ULNAR  NERVE 

Motor  Syndrome  of  Ulnar  Paralysis 

The  ulnar  nerve  supplies  : 

1.  The  flexor  carpi  ulnaris  and  the  two  internal  fasciculi  of  the  flexor 
profundus  ; 

2.  The  muscles  of  the  hypothenar  emi- 
nence ; 

3.  All   the  interossei   and  the  inner  two 
lumbricales 


Anterior  surface.  Posterior  surface. 
Fore-arm. 


Anterior  surface.  Posterior  surface. 

Hand. 


FlG,  100. — Motor  supply  of  the  ulnar. 

4.  The  adductors  of  the  thumb,  and,  partially,  the  short  flexor  of  the 
thumb  (inner  head). 


ULNAR   NERVE 


m 


i.  The  flexor  carpi  ulnaris 
is  at  the  same  time  a  flexor  of 
the  hand  on  the  fore-arm  and 
an  adductor  of  the  hand. 

If  it  is  paralysed,  flexion 
of  the  hand  remains  possible 
through  the  flexor  carpi  ra- 
dialis  and  palmaris  longus 
(median  nerve),  but  in  this 
movement  the  tendon  of  the 
flexor  carpi  ulnaris  is  no  longer 
felt  to  contract. 

Adduction  of  the  hand  is 
also  possible  by  the  extensor 
carpi  ulnaris  (musculo-spiral 
nerve),  but  it  is  greatly  weak- 
ened and  is  accompanied  by 
hyper-extension  of  the  hand. 

In  the  normal  state,  the 
tonicity  of  the  flexor  carpi 
ulnaris  produces  a  slight  in- 
clination of  the  hand  to  the 
ulnar  side  ;  its  paralysis  pro- 
duces a  slight  inclination  of 


Iendon  flexor  6ublimh 


Bifurcation. 


^Crossing  of  tendinous 
fibres. 


T.  flex,  protund. 


Insist,  flex.  sub. 


Insist,  flex.  prof. 


FlG.  102. — Action  of  flexor  profundus  in  a  patient  suffering 
from  paralysis  of  the  median,  accompanied  by  a  certain 
degree  of  articular  rigidity  of  the  fingers  offering  some  resist- 
ance to  flexion.  The  strong  contraction  of  the  flexor  pro- 
fundus causes  primarily  flexion  of  the  last  phalanges  of  the 
two  inner  fingers. 


-Flexor  tendons  and  their  insertions. 
The  superficial  flexor  is  inserted  into  the  second 
phalanx,  the  flexor  profundus  into  the  third. 


the  hand  towards 
the  radial  side. 

2.  Paralysis  of 
the  two  inner 
heads  of  the  flexor 
profundus  is  shown 
only  by  diminished 
flexion  in  the  last 
two  fingers. 

It  will  be  re- 
marked that  flexion 
of  the  second  pha- 
lanx on  the  first 
is  easily  brought 
about  (action  of 
the  superficial 

flexor  inserted  into 
the  second  pha- 
lanx). On  the 
other  hand,  flexion 


i38 


NERVE   WOUNDS 


r 


Fig.  103. — Action  of  the  inter- 
ossei  ;  flexion  of  the  first 
phalanx,  extension  of  the  last 
two  phalanges. 


of  the  last  phalanx  on  the  second  only  takes  place  in  the  case  of  the  last 

two  fingers  (action  of  the  flexor  profundus  inserted  into  the  third  phalanx). 

Complete   flexion   of  the  fingers   is   still    possible,   in  spite  of  ulnar 

paralysis.     If  it  is  weakened,  this  is  not  so 

much  from  lack  of  contraction  of  the  flexor 

profundus  as  from  paralysis  of  the  interossei, 

^m        fefeb'  \  which     are    the    true    flexors    of    the    first 

^H  -  B"  %  phalanges  on  the  metacarpus. 

^^^j  3.  Muscles  of  the  hypothenar  eminence. 

— Paralysis  of  these  muscles  is  indicated  by 

atrophy  of  the  hypothenar   eminence  ;    by 

the  disappearance  of  the  vertical  puckering 

of  the  skin  produced  by  the  palmaris  brevis  ; 

by  loss  of  the  appropriate  movements  of  the 

little  finger  produced  by  the  abductor,  the 

flexor    brevis    and    the    opponens    minimi 

digiti. 

4.  Interosseous  muscles. — All  the  in- 
terossei, both  dorsal  and  palmar,  are  supplied 
by  the  ulnar. 

Their    paralysis    is     by    far    the    most 
striking  change  produced   by  lesions  of  the 
ulnar,  for  their  role  is  most  important. 
1.  The  interossei  are  flexors  of  the  first  phalanges  on  the  metacarpus 
and  extensors  of  the  second  and  third  phalanges  on  the  first. 

In  ulnar    paralysis,  if  we  request  the  patient  to   flex  his   fingers,  we 

note     that    flexion    of    all    the 




phalanges  is  not  simultaneous. 
The  action  of  the  interossei — 
flexors  of  the  first  phalanx — is 
totally  absent  ;  flexion  first 
takes  place  in  the  last  two 
phalanges,  then  the  first  phalanx 
is  flexed  as  though  by  progres- 
sive rolling  up  of  the  fingers, 
by  traction  of  the  flexor 
muscles.  At  this  last  stage, 
however,  flexion  is  very  weak. 

Isolated  flexion  of  the  first 
phalanges,  with  extension  of 
the  last  two,  is  impossible. 

The  lumbricales  muscles,  however,  of  the  index  and  the  middle  finger 
(median  nerve),  may  partially  supply  or  make  good,  for  these  fingers,  the 
action  of  the  interossei  ;  they  are  capable  of  flexing  feebly  the  first 
phalanx  of  these  fingers  and  of  extending  the  last  two. 


Fig.  104. — The  palmar  interossei  are  adductors 
nt  the  fingers. 


ULNAR    NERVE 


*39 


2.  The  palmar  interossei  arc  adductors  of  the  fingers. 

The  dorsal  interossei  arc  abductors  of  the  fingers. 

Consequently,  the  paralysed  subject  can  neither  separate  his  fingers  nor 
bring  them  together. 

This  statement,  however,  ad- 
mits of  several  limitations.  Ob- 
servation of  these  disturbances  is 
difficult  and  requires  much  care  ; 
if  certain  precautions  are  not 
taken,  one  may  altogether  misin- 
terpret an  ulnar  paralysis,  masked 
as  it  is  by  substituted  movements. 

Indeed,  the  extensor  com- 
munis digiterum  (musculo-spiral 
nerve)  is  also  an  abductor.  The 
patient  may  therefore  separate  his 
fingers  with  his  extensors,  but 
forcible  extension  of  the  fingers 
is  also  noticed. 

On  the  other  hand,  the  flexors  of  the  fingers  are  adductors  :  conse- 
quently the  patient  may  draw  together  the  separated  fingers,  on  condition, 
however,  that  he  flex  them  slightly. 

Lateral    movements    by    the    interossei    are    accompanied    neither    by 


Fig.  105. — The  dorsal  interossei  are 
abductors  of  the  fingers. 


PlG,  106. — Ulnar  paralysis  ;  abduction  of  the  fingers  is  still  possible  by  the  action  of  the 
extensors  (musculo-spiral  nerve).  The  projections  produced  by  contraction  of  the 
extensors  are  clearly  seen. 

extension  nor  by  flexion.  They  must  be  sought  for  by  placing  the  hand 
on  a  table 'or  a  plane  surface  and  working  them"  in  a  strictly  horizontal 
plane. 


140 


NERVE   WOUNDS 


Even  in  these  conditions  we  note  that  approximation  of  index  and 
middle  ringer  is  possible  through  the  action  of  their  lumbricales  and  the 
extensor  of  the  index  which  is  slightly  adductor ;  only  the  last  two  fingers 

cannot  approach  each  other.  This  loss  of 
adduction  on  the  part  of  the  fifth  finger 
is  often  the  only  sign  that  shows  com- 
plete paralysis  of  the  ulnar ;  it  is  the 
only  movement  which  cannot  possibly  be 
simulated. 

5.  Thenar  eminence. — The  ulnar  sup- 
plies entirely  the  adductors  of  the  thumb, 
and  partially  the  flexor  brevis. 

Paralysis  of  the  adductors  can  easily 
be  discovered.  Apart  from  the  charac- 
teristic atrophy  of  these  muscles  paralysis 
of  the  adductors  is  recognised  by  the 
prehension  sign  or  the  thumb  sign  of 
Froment. 

In  order    to  grasp  a  small  object,  a 
Fig.    107.— Ulnar    paralysis;    ad-     sheet  of  paper,  for  instance,  between  the 
duction  of  the  outer  two  ringers    thumb  and  the  index,  two  movements  are 
remains  possible    by  the  lumbri-  -i  1        t?vu       *.l  •    c       1  j 

cales.      Adduction  of  the  fifth  is     P0SSlble«    Elther  the  PaPer  ,S  firml7  ?raSPed 
impossible.  between  the  body  of  the  thumb  and  the 

base  of  the  half-flexed  index  ;  thumb 
and  index  are  closely  applied  over  each  other,  mutually  fitting  into 
each  other  ;  prehension  is  energetic,  resulting  from  the  contraction  of 
the  adductor  of  the  thumb  and  from  the  inner  head  of  the  flexor  brevis 
(ulnar    nerve), — or  the    object    is    taken    between    the    extremity  of  the 


Fig.  108. — Position  of  the  thumbs  in  forcible  prehension,  in  the  case  of  a  wounded 
man  afflicted  with  left  ulnar  paralysis.      (Froment,  Presse  MeJicale,  191 5.) 


thumb  and  that  of  the  index  set  opposite  each  other  to  form  a  sort  of 
pincers,  prehension  is  then  weaker  though  more  delicate  ;  it  is  effected  by 
the  action  of  the  opponens  (median  nerve)  aided  by  the  flexor  longus 
poll  icis. 

In  ulnar  paralysis,  the  latter  type  of  prehension  is  retained  ;  to  it  the 


ULNAR   NERVE 


141 


patient  almost  always  has  recourse.  The  former  type  of  prehension  by 
adduction  is  abolished  or  rather  it  is  very  feeble  ;  the  patient  cannot  firmly 
hold  the  paper  which  he 
grasps  and  which  the  slight- 
est traction  causes  to  slip 
through  his  fingers.  This 
is  why  he  usually  has  re- 
course to  prehension  by 
opposition. 

However,  a  slight  de- 
gree of  adduction  is  gene- 
rally retained  ;  thanks  to 
the  long  extensor  of  the 
thumb  ;  but  this  action  is 
feeble,  and  is  then  accom-  Fig.  109. — Paralysis  of  ulnar  nerve  with  contraction 
panied  by  an  obvious  of  the  fingers  in  a  state  of  flexion.  Adduction  of 
,  .  the  thumb  applied  against  the  index  by  the  action 

extension       and       rotation        Qf  t^e  jong  extensor  of  the  thumb  (musculo-spiral) 
outwards  of  the  thumb.  which  is  seen  to  project.     (H.  Claude,  R.  Dumas 

and  R.  Polak,  Presse  Midicale,  191 5.) 


Sensory  Distribution — Sensory  Syndrome 

The  sensory  region  of  the  ulnar  is  far  more  definite  and   far    more 
extensive  than  that  of  the  musculo-spiral.     It  comprises  : 


Fie.  no. — Sensory  region  of  the  ulnar  (diagrammatic). 

I.  On  the  anterior  surface,  the  entire  inner  edge  of  the  hand,  separated 
from  the  region  of  the  median  by  a  vertical  line  passing  through  the 
middle  of  the  ring-finger. 


142 


NERVE   WOUNDS 


It  passes  some  centimetres  upwards  to  the  lower  and  inner  part  of  the 
fore-arm. 

2.  On  the  dorsal  surface,  the  entire  ulnar  edge  of  the  hand,  as  far  as 
to  a  vertical  line  passing  along  the  middle  of  the  middle  finger. 

It  also  extends  upwards  some  centimetres  on  to  the  ulnar  border  of  the 
fore-arm. 

The  anaesthesia  arising  from  section  of  the  ulnar  is  almost  always  very 


Fig.  hi. — Anaesthesia  in  complete  section  of  the  ulnar,  the  three  zones  correspond  to 
the  answers  given  by  the  patient,  on  examination  by  pin-prick  : 
1  st  zone,  he  replies  :  "  nothing." 
2nd  zone,  he  says  :  "  touch." 

3rd  zone,  he  says  :  "  pricks  a  little  "  (simple  hypo-resthesia). 
(Semi-diagrammatic.) 

complete,  affecting  both  the  superficial  and   the  deep  sensibilities,  mainly 
in  the  case  of  the  fifth  finger  and  the  ulnar  edge  of  the  hand. 

As  we  approach  the  middle  line,  we  notice  the  existence  of  deep 
sensation  and  tactile  hypo-aesthesia,  which,  however,  are  rarely  seen  on 
the  ring-finger  and  dorsal  surface  of  the  middle  finger,  as  a  result  of  over- 
lapping by  the  median  nerve. 


Trophic  and  Vaso-motor  Syndrome 

The  trophic  role  of  the  ulnar  nerve  is  an  important  one. 

We  are  not  now  studying  the  muscular  atrophy  which  naturally  accom- 
panies paralysis  of  the  muscles  and  gives  to  the  hand  the  characteristic 
appearance  of  ulnar  paralysis. 

We  must  also  neglect  for  the  moment  true  dislocation  of  the  hand 
which  sometimes  happens,  in  sections  of  the  ulnar  nerve,  from  atrophy  of 
the  interossei  and  relaxation  of  the  intermetacarpal  ligaments  and    carpal 


ULNAR   NERVE 


'43 


Fig.  ii2. — Lesion  of  the  ulnar  at  the  middle  part  of 
the  fore-arm.  Complete  interruption,  no  neuritic 
disturbances.  Scaly  desquamation  of  the  skin  in 
the  cutaneous  distribution  of  the  nerve. 


aponeuroses — permitting    hyper-extension    of    the    first     phalanges    and 
abnormal  mobility  of  the  metacarpals  on  one  another. 

Finally,  we  shall  not  insist  on  the  important  trophic  disturbances  which 
accompany  neuritis  of  the 
ulnar.  They  show  that 
trophic  action  does  not 
simply  extend  to  the  inner 
part  of  the  hand,  but  that  it 
may  also  reach  the  entire 
palmar  fasciae  as  well  as  the 
synovial  membranes  and 
fibrous  tendon  sheaths  of 
the  flexors  of  middle  finger 
and  index  ;  consequently 
going  far  beyond  the  cutan- 
eous region  of  the  nerve. 
This  is  readily  understood 
when  we  remember  the 
course  of  the  deep  palmar 
branch  which  would  seem 
to  play  an  important  trophic  role. 

Simple  suppression  of  the  functions  of  the  ulnar,  in  complete  section  of 
the  nerve,  for  instance,  often  shows  cutaneous  trophic  disturbances  and 
interesting  vascular  changes. 

Very  frequently  there  is 
found  a  state  of  dryness  of 
the  skin  throughout  the  entire 
distribution  of  the  nerve;  it 
is  sometimes  accompanied  by 
a  branny  desquamation  or 
even  by  an  active  scaly  ap- 
pearance, limited  to  the  cuta- 
neous region  of  the  ulnar. 

In  complete  interruptions 

of  the    ulnar,    we    may   find 

ulcerations,  readily  provoked 

FiG.  113. — Section  of  the  ulnar  above  the  epitroch-     by      slight       injuries,      burns, 

lea        Trophic  ulcers  that   have  appeared    as  a     cnilblainS,  galvanic  baths,  etc. 

result  or  a  simple  galvanic  bath,  01  slight  intensity  '  c  ' 

(10  to  15  milliamperes).  Their  slow  rate  of  healing  is 

a  sign   of  special  fragility  of 
the  skin  and  of  insufficient  trophic  action. 

Finally  we  often  notice  a  certain  degree  of  redness  or  cyanosis  in  the 
inner  two  fingers  and  particularly  in  the  fifth.  This  appearance  is  some- 
times extremely  pronounced  ;  we  see  the  little  finger  swollen,  shining  with 
a  bright  red  or  a  dark  violet  tint,  which  would  almost  suggest  a  vascular 


144  NERVE    WOUNDS 

obliteration.  These  vascular  disturbances  are  chiefly  found  in  those  who 
are  predisposed  to  cyanosis  of  the  extremities  ;  they  are  really  no  more 
than  a  local  exaggeration,  favoured  by  vaso-motor  paralysis. 

We  may  compare  with  this  fact  the  frequency  of  chilblains  found  in 
predisposed  subjects,  in  the  distribution  of  the  nerve. 

TYPES  OF   ULNAR   PARALYSIS 

The  ulnar  being  essentially  a  nerve  of  the  hand,  the  disturbances  of 
which  are  rarely  manifested  except  in  movements  of  the  fingers,  there  is 
no  occasion  to  examine  in  detail,  as  in  the  case  of  the  musculo-spiral 
nerve,  the  syndromes  resulting  from  lesion  of  the  nerve  at  different  levels. 

Whatever  the  seat  of  the  lesion,  the  posture  and  the  motor  dis- 
turbances are  approximately  the  same.  The  various  syndromes  result 
mainly  from  the  nature  of  the  inquiry,  complete  or  incomplete  inter- 
ruption, nerve  irritation  or  dissociated  lesion.  In  passing,  we  will  simply 
indicate  the  slight  differences  which  distinguish  injuries  of  the  nerve 
above  the  epitrochlea  from  interruptions  in  the  fore-arm  below  the  flexor 
carpi  ulnaris  and  the  flexor  profundus  muscles. 

I.— SIMPLE  COMPRESSION  OR  RECENT  INTERRUPTION 

OF   THE    ULNAR 

Paralysis  of  the  ulnar  is  often  difficult  to  recognise  in  these  conditions  ; 
it  is  frequently  overlooked  because  of  the  numerous  muscular  substitutions 
we  have  studied  above. 

It  must  be  remembered  that  flexion  of  the  fingers  is  preserved  by 
means  of  the  superficial  flexor  and  the  two  external  tendons  of  the  flexor 
profundus  (median).  Minute  examination  is  needed  to  see  that  it  was 
weakened  :  this  weakening  is  the  result,  first,  of  paralysis  of  the  two  inner 
heads  of  the  flexor  profundus  (flexion  of  the  third  phalanx  on  the  second 
does  not  take  place) ;  second,  of  paralysis  of  the  interossei,  powerful  flexors 
of  the  first  phalanx.  This  causes  great  difficulty  in  performing  movements 
that  require  considerable  flexion  of  the  first  phalanges  along  with  ex- 
tension of  the  other  two  (difficulty  and  fatigue  in  writing). 

Extension  of  the  last  two  phalanges  on  the  first  (interossei)  is  still 
possible,  though  feeble,  in  the  case  of  the  index  and  the  middle  finger  by 
means  of  the  lumbricales  (median). 

Separation  of  the  fingers  (dorsal  interossei)  may  be  effected  by  substi- 
tution of  the  extensors. 

Adduction  of  the  fingers  (palmar  interossei)  is  possible,  though  weak, 
by  the  action  of  the  flexors,  or  laterally,  by  the  lumbricales  of  the  index  and 
the  middle  finger. 

Adduction  of  the  thumb  has  disappeared  (although  imperfectly  replaced 
by  substitution  of  the  long  extensor),  but  opposition  still  exists  (median), 


ULNAR    NERVE 


'45 


and  a  methodical  examination  is  required  to  distinguish   them,  by  investi- 
gation of  the  prehension  sign  of  the  thumb. 

In  these  conditions,  ulnar  paralysis  may  frequently  pass  unnoticed  on  a 
superficial  examination. 


Fir,.   1 14. — Complete  section  of  the  ulnar  above  the  epitrochlea  (photograph  taken  two 
months  after  the  wound).     Hand  in  a  state  of  rest,  simple  type  of  ulnar  griffc. 

The  position  is  not  so  clearly  characteristic  as  one  might  expect  from 
the  classical  description. 


Ph..  115. — Same  figure  as  above,  with  maximum  extension. 


Ulnar  griffc  is  often  scarcely  perceptible. 

The  hand  is  somewhat  flattened  ;   the  hypothenar  eminence  is  slightly 
atrophied,  as  are  the  adductors  of  the  thumb. 

10 


146 


NERVE   WOUNDS 


We  see  when  the  hand  is  at  rest  that  the  fifth  finger  is  slightly  flexed, 
also  the  fourth,  though  in  less  degree. 

This  slight  flexion  of  the  inner  two  fingers  is  due  to  suppression  of  the 
interossei,  extensors  of  the  last  two  phalanges  ;  the  fingers  become  flexed 
owing  to  the  tone  of  the  superficial  flexor. 

If  the  patient  is  requested  to  extend  vigorously  his  hand  and  fingers, 
the  attitude  is  not  much  more  characteristic. 

We  note  that  extension  is  not  absolutely  complete  ;  the  hand  is  but 
partially  extended.  The  fifth  digit  is  still  slightly  flexed,  as  well  as  the 
fourth  ;  but  the  other  fingers  are  extended,  and  we  must  test  their 
resistance    when    extended  to  ascertain   that   extension    of  the    last    two 


Fig.  116. — -Lesion  of  the  ulnar  above  the  epitrochlea  (complete  section  three  months 
previously).  Typical  ulnar  griffe  which  gradually  appeared  about  six  weeks  after 
paralysis.  Note  the  marked  flexion  of  the  second  phalanx  on  the  first,  whilst  the  third 
is  but  slightly  flexed  on  the  second.  Tonic  action  of  the  superficial  flexor  (second 
phalanx),  paralysis  of  the  flexor  profundus  (third  phalanx). 

phalanges    is    very   feeble,    and   merely   the    result    of  contraction   of  the 
lumbricales. 

Nevertheless,  if  ulnar  paralysis  persists  long  enough,  hypotonia  of  the 
interossei  becomes  pronounced,  and  there  takes  place  the  typical  ulnar 
griffe  with  semi-flexion  of  the  fourth  and  particularly  the  fifth  fingers. 
This  flexion  affects  almost  exclusively  the  second  phalanx  (superficial 
flexor)  ;  the  third  phalanx  (flexor  profundus)  remains  almost  fully  extended. 


The  description  just  given  of  ulnar  griffe  in  recent  sections  or 
compressions  of  the  nerve,  applies  mainly  to  injuries  above  the  epitrochlea. 

If  the  nerve  is  injured  below  the  motor  branches  which  it  supplies  to 
the  flexor  profundus  and  extensor  carpi  ulnaris,  the  position  of  the  hand  is 
slightly  different. 


ULNAR    NERVE 


'47 


The  ulnar  griffe  occurs  earlier  and  is  more  pronounced.  It  becomes 
obvious  owing  to  preservation  of  the  flexor  profundus.  (J.  and  A. 
Dejerine  and  Mouzon.) 

No  longer  does  it  consist  of  simple  flexion  of  the  second  phalanx  on  the 
first  ;  the  third  phalanx  is  also  flexed. 

The  role  of  the  flexor  profundus  in  ulnar  griffe  is  clearly  shown  in  the 
course  of  nerve  regeneration  ;  thus,  in  a  section  of  the  ulnar  above  the 
epitrochlea,  we  find  ulnar  griffe  but  faintly  perceptible,  as  long  as  the  flexor 
profundus  remains  paralysed  ;  then,  with  the  growth  of  the  axis-cylinders 
and  the  return  of  tonicity  and  contractility  in  the  flexor  profundus  the 
claw-like  attitude  of  the  last  two  fingers  is  seen  to  take  shape  and  to 
become  pronounced. 


FlG.  i  17. — Ulnar  paralysis  (nerve  in  course  of  regeneration)  through  lesion  of  the  nerve 
above  the  epitrochlea  (complete  section,  suture  of  the  nerve  two  months  after  the 
wound)  ;  ulnar  griffe  has  graduallyappeared  acquiring  the  typical  form,  about  two  months 
after  the  wound.  Three  months  after  suture,  it  has  become  modified  by  progressive 
flexion  of  the  third  phalanx,  the  flexor  profundus  having  regained  its  tone  and  its 
function*.     (Note  the  projection  of  the  tendon  of  the  flexor  carpi  ulnaris. ) 

Finally,  adduction  with  flexion  of  the  hand,  which  is  effected   by  the 
flexor  carpi  ulnaris,  is  of  course  retained. 


In  all  these  cases,  ulnar  griffe  caused  by  recent  injury  of  the  nerve, 
whether  resulting  from  lesion  above  or  below  the  flexor  profundus,  is 
always  slight  ;  it  is,  moreover,  essentially  a  soft,  supple,  easily  reducible 
Sr'ffi'-       (J-  and  A.  Dejerine  and  Mouzon.) 

It  is  due  entirely  to  loss  of  power  and  tone  of  the  interossei  ;  there  is 
no  fibrous  contraction  whatsoever  keeping  the  fingers  flexed,  as  may  happen 
sometimes  in  complete  and  long-standing  interruptions.  We  do  not  find 
the  fibrous,  intractable,  irreducible  transformation  which  characterises  the 


i48 


NERVE   WOUNDS 


ulnar  griffe  of  nerve  irritation,  resulting  from  contraction  of  the  muscles 
and  tendons,  from  fibrous  transformations  of  the  palmar  aponeurosis  and 
the  adhesions  contracted  between  the  tendons  and  their  synovial  sheaths. 


Figs.  118  and  119. — Ulnar  griffe  caused  by  complete  section  or"  nerve  in  fore-arm 
(5  months).  This  is  a  soft,  easily  reducible  griffe,  as  in  all  cases  of  complete  inter- 
ruption, with  the  exception  of  very  slight  flexion  of  the  fifth  linger  caused  by  fibrous 
contraction  of  the  tendon. 


It  may  be  established  as  an  almost  absolute  principle  that  every  fibrous 
griffe  is  of  neuritic  origin,  without  complete  interruption  of  the  nerve  ;  it  is 
always  accompanied  by  pain  on  pressing  the  muscles  and  nerve  trunk  and 
by  some  trophic  disturbances. 


ULNAR    NERVE 


149 


II.— SYNDROME   OF   PROLONGED   COMPLETE 
INTERRUPTION 

It  is  somewhat  difficult,  during  the  first  two  or  three  months,  to 
distinguish  the  syndrome  of  interruption  from  that  of  compression,  which 
moreover  is  far  rarer  in  the  ulnar  than  in  the  musculo-spiral. 

The  main  points  in  this  diagnosis  are,  as  in  the  other  nerves,  the  far 
greater  rapidity  and  intensity  of  hypotonia  and  muscular  atrophy  ;  the  fixity 
of  sensory  disturbances,  the  more  rapid  and  complete  appearance  of  the 
RD  ;  the  existence  of  formication  in  a  fixed  zone,  at  the  level  of  the  lesion, 
and  the  analgesia  of  nerve  and  muscles. 

After  two  to  three  months,  however,  complete  interruption   is  more 


Fig.  120. — Hyper-extension  of  the  last  two  fingers  (by  hypotonia  of  the  interossei) 
in  prolonged  ulnar  paralysis. 

strikingly  shown  by  muscular  atrophy  and  by  the  greater  hypotonia  of  the 
interossei. 

1.  This  hypotonia  of  the  interossei  is  at  times  so  pronounced  and 
accompanied  by  so  much  articular  relaxation  that  abnormal  movements  are 
produced. 

First,  we  have  hyper-extension  of  the  first  phalanges,  brought  on 
without  effort,  when  the  patient  tries  to  extend  his  fingers  or  when  an 
attempt  is  made  to  obtain  this  hyper-extension  by  passive  movements  ;  it 
may  be  quite  extraordinary  in  certain  patients.  Indeed,  Duchenne  of 
Boulogne  has  shown  that  the  action  of  the  interossei  alone,  forming  by 
their  tendons  a  sort  of  band  on  the  dorsal  surface  of  the  metacarpals, 
opposes  hyper-extension  of  the  fingers. 

This  hyper-extension  maybe  limited  to  or  most  pronounced  in  the  last 
two  fingers;  but  it  may  also  show  itself  in  the  last  three  or  even   in  all 


150 


NERVE   WOUNDS 


four  fingers  when   the   lumbricales  of  index  and    middle  finger  become 
incapable  of  fulfilling  their  function  as  substitutes  for  the  interossei. 

Atrophy  and  laxity  of  the 
articular  ligaments  is  in  these  cases 
associated  with  hypotonia  of  the 
muscles. 

Palpation  of  the  hand  shows 
such  relaxation  of  the  inter-meta- 
carpal  ligaments  as  enables  the 
bones  of  the  metacarpo-phalangeal 
articulations  to  move  freely  upon 
one  another,  affording  a  sensation 
of  extreme  laxity  and  genuine  dis- 
location of  the  metacarpus.  This 
articular  laxity  is  far  greater  in  the 
ulnar  part  of  the  hand,  though  it 
should  be  noted  in  the  normal 
state  that  there  is  greater  laxity  in 
these  same  articulations  of  the 
fourth  and  fifth  meta-carpals. 

2.  At    the    same    time,    ulnar 
griffe   becomes    pronounced,    as    a 
result   of  increasing  hypotonia  of 
the    interossei  ;     it     assumes    the 
appearance  described  by  writers  on  the  subject.     The  last  two  fingers  are 


Fig.  121. — Dislocation  of  the  metacarpus. 
Lateral  compression  of  the  hand  gives  it  a 
cylindrical  form. 


Fig.  122. — Long-standing  (5  months)  ulnar  paralysis,  complete  interruption  above 
the  epitrochlea,  typical  griffe. — Flexion  of  second  phalanx  only. 


flexed  almost  completely  into  the  palm  of  the  hand,  and  this  attitude  is  even 


ULNAR    NERVE 


151 


Fig.  123. — Long-standing  (three  months)  ulnar 
paralysis  (lesion  at  the  middle  third  of  fore- 
arm), complete  interruption,  accentuation  of 
typical  griffc. 


more  marked  if  the  nerve  is  aftccted  below  the  flexor  profundus.  In  this 
case  also,  the  third  phalanx  naturally  participates  in  the  flexion. 

Flexion  of  the  last  two  fingers  affects  the  middle  finger  slightly,  owing 
to  the  slips  of  the  palmar 
aponeurosis  which  unite  the 
third  and  fourth  fingers  at 
their  bases  ;  and  if  the 
lumbricales  finally  weaken  in 
their  resistance,  the  index 
also  becomes  flexed,  thus  pro- 
ducing a  sort  of  incomplete 
three-fingered  or  even  four- 
fingered  griff?. 

We  find  that  the  lumbri- 
calis  of  the  middle  finger, 
normally  supplied  by  the 
median,  may  also  sometimes 
be  supplied  by  the  ulnar. 

In  all  cases  this  gr'iffe 
remains  flaccid  and  reducible. 

It  is  solely,  we  must  repeat,  nerve  irritation  of  the  ulnar  that  creates 
the  irreducible  griffes.  Still,  in  some  cases,  we  see  that  there  occurs 
a  slight   fibrous  contraction   of  the   flexor  tendons,  which  fixes  the  fifth 

finger  and  to  some  ex- 
tent also  the  ring-finger, 
in  a  moderate  curvature. 
In  all  these  cases  of 
complete  and  long-stand- 
ing interruption,  we  are 
struck  by  the  relatn  e 
unimportance  of  trophic 
disturbances.  The  skin 
is  dry  and  often  becomes 
the  seat,  on  the  palmar 
surface  especially,  of  a 
sort  of  branny  desquama- 
tion ;  but  the  integu- 
ments remain  supple,  the 
nails  are  not  deformed, 
and  the  articulations  re- 


Fig.  124. — Long-standing  (five  months)  ulnar  paralysis 
(lesion  at  the  upper  third  of  fore-arm),  three-fingered 
griffe  through  weakening  of  the  lumbricales  or  perhaps 
innervation  by  the  ulnar  of  the  second  lumbricalis, 
ordinarily  supplied  by  the  median. 


tain  their  mobility.  Only  vascular  disturbances,  and  particularly  cyanosis 
which  is  distinctly  confined  to  the  region  of  the  affected  nerve,  can  be 
seen  ;  the  frequency  of  chilblains,  the  easy  production  of  accidental  ulcers 
and  the  slowness  of  their  cicatrisation  alone  hear  witness  to  the  important 
effects  upon  nutrition  of  the  tissues. 


152 


NERVE    WOUNDS 


In  some  cases,  however,  we  have  found  extremely  important  vascular 
disturbances  of  the  little  finger,  which  becomes  swollen  and  shining,  and 
offers  an  almost  black  cyanotic  appearance,  as  though  caused  by  a  sort  of 


Fig.  125. — Long-standing  (six  months)  ulnar  paralysis  (wrist  wound,  complete  section), 
four-fingered  griffe  from  weakness  of  the  lumbricales  ;  flaccid  griffe. 

exaggerated   paralytic  stasis.     Possibly,  in  these  cases,  disuse  of  the  hand 
may  have  favoured  the  appearance  of  such   intense  vascular  disturbances. 


Fig.  126. — Hyper-extension  of  the  first  phalanges  in  preceding  case,  from  relaxation  ot 
metacarpophalangeal  articulations,  hypotonia  of  interossei  and  projection  ot 
extensors. 


They  are  never  found   in   patients  treated   by  massage,  mobilisation  and 
electricity. 


ULNAR    NERVE 


153 


Fig.  127. — Atrophy  of  the  hypothenar  eminence. 


3.  Lastly,  muscular  atrophy  is  pronounced.  The  flattening  of  the 
hypothenar  eminence  is  complete  ;  paralysis  of  these  muscles,  particularly 
of  the  palmaris  brevis,  does  away  with  the  creases  of  the  skin  and  its  vertical 
contraction.  The  atro- 
phied interossei  produce 
on  the  dorsal  surface  ot 
the  hand  actual  intermeta- 
carpal furrows  ;  exaggera- 
tion of  these  furrows  may 
produce  quite  a  skeleton 
hand  ;  the  adductors  of 
the  thumb  disappear,  leav- 
ing between  thumb  and 
index  a  deep  depression  in 
which  palpation  of  the 
first  interosseous  space  re- 
veals nothing  but  a  thin 
muscular  sheet  almost 
devoid  of  substance. 

The  thenar'eminence  in   its  deep  layers,  becomes  flattened,  the  thumb 

lies  close  against  the  index  on  the 
same  plane  though  twisted  some- 
what outwards,  bringing  its  palmar 
surface  on  to  the  outer  side  of  the 
index  (predominance  of  the  op- 
ponens). 

It  is  in  these  cases  of  atrophy 
and  extreme  hypotonia  of  the  ad- 
ductors of  the  thumb  and  inner  slip 
of  the  flexor  brevis,  that  we  some- 
times meet  with  the  attitude  de- 
scribed by  Jeanne.*  This  is  a  sort 
of  thumb  griffk)  characterised  by 
extension  of  the  first  phalanx  ami  by 
semi-flexion  in  the  second. 

The  adductors  of  the  thumb  and 
the  flexor  brevis  are,  like  the  inter- 
ossei, though  to  a  less  degree,  flexors 
of  the  first  phalanx  and  extensors 
of  the  second,  through  the  dorsal 
slip  which  the}'  send  to  the  extensor 
tendons. 

This  attitude,  however,  is  rare,  for  the  external  slip  of  the  flexor  bre\  is 
(median),  which  has  the  same  action,  is  usually  capable  ot  correcting  it. 
*  Jeanne.     Societe  de  Chirurgie,  \~  March,  1915. 


Fig.  12S. — Atrophy  of  the  interossei. 


154 


NERVE   WOUNDS 


Fig.  129. — Atrophy  of  the  adductors  of  the  thumb. 


Atrophy  of  the  interossei,  so  clearly  significant  of  paralysis  of  the  ulnar, 

persists  long  after  the 
cure  of  this  paralysis. 
It  also  exists  in  certain 
incomplete  lesions  of 
the  ulnar  and  enables 
us  to  recognise  them, 
even  in  the  absence  of 
definite  paralysis. 

III.— SYNDROME 
OF  NERVE  IRRI- 
TATION 

It  is  nerve  irritation 
that,    more    than   any- 
thing else,  creates  the  fibrous  griffes  of  the  ulnar. 

In  these  cases,  to  a  more  or  less  marked  extent,  we  find  spontaneous 
pains  in  the  distribution  of  the 
nerve,  pain  caused  by  pressure  on 
the  nerve  trunk,  painful  anaes- 
thesia of  the  skin,  or  even  com- 
plete hyper-aesthesia  ;  pressure 
on  the  antibrachial  muscles  and 
especially  on  the  hypothenar 
eminence,  and  compression  be- 
tween two  fingers  of  the  adduc- 
tors of  the  thumb,  cause  very 
keen  suffering. 

The  painful  syndrome  is  more 
or  less  pronounced,  as  the  case 
may  be ;  it  seldom,  however,  at- 
tains the  degree  of  certain  cases 
of  neuritis  of  the  median.  It 
may  be  found  without  very 
evident  paralysis,  though  it  is 
almost  always  accompanied  by 
important  trophic  disturbances. 

The  scaly  condition  of  the 
skin,  infiltration  of  the  dermis, 
woody   atrophy    of  the    muscles 

and     the     split     curved     State    of    Flp-    130—  Neuritic   ulnar  griff,-,  fibrous  and 
.  ..  .  inextensible  ;  pain  by  pressure  on  the  hypo- 

trie      nails,     are      more      or      less  thenar  and  interosseous  .nuscles.    Maximum 

Striking.  extension.    Contraction  of  the  flexor  tendinis. 

The  more  rapid  growth  of  the 
nails  raises  the  pulp  of  the  finger  into  a  small  sub-ungual  and   frequently 


ULNAR    NERVE 


155 


painful  tumour,  the  presence  of  which   is  an   indication  of  neuritis,  how- 
ever slight. 


Fig.  131. — Contraction  of  the  palmar  aponeurosis  in  a  neuritic  ulnar  griffe 
(four-fingered  griffe). 


Fig.  132. — Neuritic,  irreducible,  ulnar  griff  1 ' :  contraction  of  flexor  tendons 
and  palmar  aponeurosis. 


156 


NERVE    WOUNDS 


The  main  points  to  note,  however,  are  :  fibrous  contraction  of  the 
flexor  tendons,  adhesion  of  the  tendons  to  the  synovial  sheaths,  thicken- 
ing and  fibrous  contraction  of  the  palmar  aponeurosis,  comparable 
to  Dupuytren's  contracture,  the  prominences  of  which  stand  out  like 
whipcord. 

These  lesions  emphasise,  intensify  and  render  irreducible  the  attitude 
of  ulnar  griffe. 

It  may  be  affirmed  that  every  fibrous  and  irreducible  ulnar  griffe  is  a 
sign  of  more  or  less  pronounced  nerve  irritation. 

This  is  easily  demonstrated  ;  whenever  we  find  a  fibrous,  inextensible, 
or  even  moderate  griffe,  we  need  only  pinch  between  two  fingers  the  mass 
of  hypothenar  muscles  or  the  adductors  of  the  thumb,  to  cause  a  very  acute 
sensation  of  pain. 

Frequently  the  griffe  is  confined  to  the  ulnar  part  of  the  hand  and 
reaches  only  the  ring-finger  and  the  fifth  finger  ;  at  most  it  involves  the 


Fig.  134. — Disturbances  of  sensibility 
in  the  same  case  of  neuritis  combined 
with  fibrous  griffe,  without  paralysis. 

middle  finger  in  slight  flexion. 
Sometimes  also  it  invades  the 
entire  palmar  aponeurosis  and 
produces  a  veritable  three-fingered 
or  four-fingered  griffe. 

Neuritis    of    the    ulnar    may 
show   itself  without  paralysis,  or 

Frc.  133.— Neuritic  griffe   of  ulnar   without     with  onl.v  PartiaI  paralysis,  cither 

paralysis  of  the    interossei,   combined    with     owillii;   to    the  fact    that  the  slight 

fibrous  infiltration  of  the  palmar  aponeurosis     •     •.    .•         1     •         1    _    „_.    «-^,,^korl 
.        .      ..        ,  .,    a  r     .     ,'  irritative   lesion   has  not  touched 

and  contraction  01  the  flexor  tendons. 

the    motor     fibres,    or     that     the 

trophic  fibres  form  a  distinct  fasciculus  which  the  lesion  can  reach,  whilst 

leaving  the  motor  fibres  untouched. 

For    instance,   we  may  mention   the   case    of  a  patient  afflicted  with 


ULNAR    NERVE 


157 


lesion  of  the  ulnar  at  the  middle  third  of  the  fore-arm.  There  was  no 
paralysis  of  the  interossci,  for  the  muscles  possessed  their  normal  electrical 
reactions  and  the  patient  was  able  to  do  all  the  movements,  though  not  to 
the  full  extent.  On  the  other  hand,  along  with  complete  anaesthesia  in 
the  ulnar  area,  there  was  nerve  irritation  producing  fibrous  transformation 
of  the  sub-cutaneous  cellular  tissue  and  of  the  palmar  aponeurosis, 
contraction  of  the  flexor  tendons  and  adhesion  to  the  synovial  sheaths. 
To  such  a  degree  was  this  the  case  that,  in  spite  of  the  integrity  of  the 
interossei,  their  movements  were  rendered  painful  and  strictly  limited  by 
the  fibrous  transformation  of  the  hand  in  its  ulnar  part. 

In  another  case,  a  slight  lesion  of  the  ulnar  only  after  some  months 


Fig.  135. — Contraction  of  the  palmar  aponeurosis  which  has  gradually  appeared  after 
slight  irritation  of  the  ulnar.  No  paralysis  ;  scarcely  perceptible  hypo-resthesia.  I  he 
little  finger  is  habitually  flexed  on  the  hand  ;  the  semi-flexion  lure  represented  can  be 
obtained  only  by  exercising  very  strong  traction  which  raises  beneath  the  skin  the 
knotty  projections  of  the  contracted  aponeurosis. 

produced  a  slow  and  progressive  contraction  of  the  palmar  aponeurosis, 
exactly  comparable  with  that  of  Dupuytren's  contracture,  which,  after  all, 
is  probably  due  to  nothing  more  than  slight  neuritis  of  the  ulnar  or  of  its 
component  cervical  roots. 

We  shall  soon  see  that  slight  neuritis  of  the  ulnar  may  frequently  cause 
states  of  muscular  hypertonia  or  of  contraction,  producing  paradoxical 
attitudes.  We  ought  to  mention  the  special  tendency  of  the  ulnar  nerve 
to  cause,  through  slight  irritation,  contraction  of  the  muscles  of  the  hand  ; 
this  nerve  is  found  to  be  affected  in  most  of  the  cases  that  produce  the 
"  accoucheur  "  type  of  hand.  These  states  of  hypertonia,  however,  through 
irritation  of  the  ulnar,  are  really  somewhat  complex  :  we  will  study  them 
separately,  after  the  diagnosis  of  ulnar  paralysis. 

Nerve  irritation  of  the  ulnar  is  often  a  serious  complication,  certainly 
more  serious  than  total  interruption.     Whereas  paralysis    from  complete 


158  NERVE   WOUNDS 

interruption  readily  permits  of  the  use  of  the  hand,  owing  to  the  many 
substitutions,  neuritis  of  the  ulnar  renders  the  patient  quite  powerless. 
After  suture,  the  interrupted  ulnar  nerve  will  gradually  regain  its  functions, 
whilst  neuritis  may  create  irreparable  fibrous  contractions. 


IV.-NEURALGIA   OF   THE   ULNAR 

Slight  lesions  of  the  ulnar  are  sometimes  indicated  by  painful  syndromes, 
of  the  simple  neuralgic  type,  associated  or  unassociated  with  motor 
disturbances  but  not  accompanied  by  the  trophic  disturbances  which 
characterise  nerve  irritation.  This  neuralgia  of  the  ulnar  is  seldom  as 
intense  as  that  of  the  median.  There  may,  however,  be  found,  more 
especially  in  lesions  affecting  the  ulnar  at  the  upper  part  of  the  arm, 
painful  syndromes  of  the  causalgic  type;  intensity  of  the  pain,  extreme 
hyper-aesthesia  of  the  skin,  radiation  of  the  pain  over  the  whole  limb  even 
above  the  lesion,  the  provocation  of  pain  by  the  slightest  contacts  or  even 
by  vivid  impressions  and  emotions  :  all  these  recall  the  characteristics  of 
median  causalgia. 


V.— DISSOCIATED   SYNDROMES 

Like  all  the  other  nerves,  the  ulnar  is  composed  of  distinct  fasciculi, 
destined  for  a  special  trophic,  sensory  or  motor  region. 

Investigation  of  the  many  cases  observed  during  the  war  has  enabled 
us  to  outline  the  study  of  this  fascicular  topography. 

The  possibility  of  partial  lesions  producing  dissociated  syndromes  is  one 
result  of  this  investigation. 

For  instance,  a  lesion  of  the  ulnar  nerve  in  the  arm,  affecting  the 
external  part  of  the  nerve,  may  cause  nothing  more  than  paralysis  of  the 
flexor  profundus  and  of  the  flexor  carpi  ulnaris,  leaving  the  interossei 
untouched.  On  the  other  hand,  lesion  of  the  nerve  in  its  internal, 
superficial  part,  may  be  indicated  solely  by  paralysis  of  the  interossei  and 
of  the  hypothenar  eminence,  the  flexor  profundus  and  the  flexor  carpi 
ulnaris  being  preserved. 

The  mutual  positions  of  the  principal  fasciculi  are  thus  known  by 
superposition  of  various  clinical  cases,  as  also  by  direct  electrical  stimulation 
of  the  fasciculi  of  the  nerve  in  the  course  of  surgical  operations.  (P. 
Marie  and  Meige.) 

It  is  now  known  that,  above  the  elbow,  the  fibres  destined  for  the  flexor 
carpi  ulnaris  and  for  the  flexor  profundus,  as  well  as  those  destined  for  the 
adductor  of  the  thumb,  occupy  the  external  part  of  the  nerve,  and 
consequently  lie  on  the  inner  surface  of  the  humerus. 

On  the  other  hand,  the  sensory  fibres  and  the  motor  fibres  destined  for 


ULNAR   NERVE  159 

the  hypothenar  eminence  and  for  the  last  interossei,  occupy  the  internal 
part  of  the  nerve  ;  they  are  therefore  superficial  and  more  exposed  to  be 
affected  by  partial  traumatisms.     (Dejerine.) 

This  arrangement  probably  explains  why  certain  lesions  of  the  nerve 
above  the  elbow  are  accompanied  by  more  or  less  marked  ulnar  griff  e — 
according  as  the  fasciculi  destined  for  the  flexor  profundus  have  been 
attacked  or  not.  Ulnar  griffe  will  be  more  pronounced  in  cases  where  the 
flexor  profundus  is  untouched  ;  indeed,  it  collaborates  with  the  superficial 
flexor  in  flexing  the  second  and  third  phalanges  of  the  fingers  whose 
extensors  are  mainly  the  interossei. 

In  the  fore-arm  also  are  found  lesions  confined  to  the  internal  part  of 
the  ulnar  nerve,  which  are  characterised  by  intense  sensory  and  trophic 
disturbances,  along  with  relative  preservation  of  the  interossei  ;  in  these 
cases,  it  is  again  the  muscles  of  the  hypothenar  eminence  and  the 
interossei  of  the  last  spaces  that  are  most  affected.  On  the  other  hand,  the 
fibres  destined  for  the  interossei  of  the  first  spaces  and  for  the  adductors  of 
the  thumb  appear  to  occupy  the  external  part  of  the  nerve. 

According  to  J.  and  A.  Dejerine  and  Mouzon,  then,  we  may  sum  up 
as  follows  the  fascicular  topography  of  the  ulnar.  From  within  outwards 
we  find — 

1.  The  sensory  cutaneous  branches  and  the  branches  of  the  hypothenar 
eminence,  entirely  superficial. 

2.  The  fasciculi  destined  for  the  interossei  representing  the  deep 
palmar  branch  of  the  ulnar.  The  fibres  destined  for  the  different  inter- 
osseous muscles  are  also  arranged  in  layers  from  within  outwards  :  the 
fibres  of  the  last  interossei  are  the  most  internal. 

3.  The  fibres  of  the  adductors  of  the  thumb  occupy  on  the  fore-arm 
the  most  external  position  ;  this  muscle,  indeed,  represents  the  inter- 
osseous of  the  first  space.  On  the  arm,  it  is  also  external,  though  still 
covered  by  the  fibres  of  the  flexor  carpi  ulnaris  and  of  the  flexor  profundus. 

4.  The  fasciculi  of  the  flexor  carpi  ulnaris  and  of  the  flexor  profundus 
which  occupy  at  the  level  of  the  arm  the  most  external  part  of  the  ulnar 
nerve. 

In  the  case  of  the  ulnar,  as  of  all  the  other  nerves,  one  cannot  help 
being  struck  by  the  way  in  which  the  fascicular  topography  is  identical 
with  the  root  topography  of  the  sensory  and  motor  regions.  There  is,  so 
to  speak,  in  the  nerve  a  sort  of  relative  lengthening  of  its  root  constitution  ; 
for  instance,  the  fibres  destined  for  the  adductors  of  the  thumb  which 
seem  mostly  to  originate  in  the  eighth  cervical  root  are  more  external 
than  the  fibres  of  the  hypothenar  eminence,  supplied  by  the  first  dorsal 
root. 

We  here  give  as  an  instance  of  dissociated  syndromes  the  following 
two  contrasted  cases,  a  study  of  which  has  proved  to  J.  and  A.  Dejerine 
and  Mouzon  the  fascicular  topography  of  the  ulnar. 


160  NERVE   WOUNDS 

Fig.  136.* — State  of  soldier  Vid  .  .  .,  2  Nov.,  1914,  74th  day  after  his  wound — 
Keloid  occupying  the  internal  third  of  the  right  ulnar  nerve  in  the  arm  (partial  lesion). 
(Shown  at  the  Societe  de  Neurologie,  3  June,  1915.) 

Soldier  Vid  .  .  .,  of  the  1st  Zouaves,  wounded  on  the  8th  Sept.,  1914,  at  Sezanne,  by 
Mauser  bullet (?).  The  ball  crossed  the  inner  region  of  the  right  arm,  two  fingers' 
breadths  above  the  epitrochlea.  Immediate  ulnar  paralysis.  There  can  be  lelt,  through 
the  skin,  along  the  track  of  the  bullet,  an  indurated  swelling  of  the  ulnar  nerve. 

Operation,  21  Dec  .  1914  (104th  day  after  the  wound),  by  Dr.  Gosset.  Indurated 
swelling,  6  to  8  mm.  long,  forming  a  projection  on  the  inner  surface  of  the  ulnar  nerve, 
along  the  track  of  the  bullet.  This  projection  was  adherent  to  the  skin.  It  was  first  cut 
oft  flush  with  the  inner  surface  of  the  nerve.  Then  the  indurated  nucleus,  which  seemed 
to  act  as  a  kind  of  root  in  the  interior  of  the  nerve  itself,  was  extracted.  After  ex- 
traction of  this  nucleus,  there  was  found  to  be  a  notch  on  the  inner  third  of  the  ulnar. 
The  fasciculi,  which  were  interrupted  at  the  level  of  this  notch,  were  not  sutured. 

Slow  progress  as  regards  movement,  with  appearance  of  amyotrophy,  following  suture, 
and  coinciding  with  the  first  phenomena  of  motor  restoration.  Scarcely  any  ameliora- 
tion in  the  disturbances  of  objective  sensation,  five  and  a  half  months  after  the  operation. 

a,  Attitude  of  the  hand  at  rest  (disturbances  of  tone).     Note  : 

1.  That  the  hand  remains  inclined  towards  the  ulnar  side,  the  normal  type  (good 
tone  of  the  flexor  carpi  ulnaris). 

2.  That  there  exists  a  certain  degree  of  <:  ulnar  griffe"  This  attitude  seems  due  to 
the  tone  of  the  flexors  of  the  last  two  fingers,  and  particularly  of  the  deep  flexors,  which 
is  greater  than  the  tone  of  the  corresponding  interossei. 

3.  That  atrophy  seems  more  pronounced  in  the  hypothenar  eminence  than  in  the 
adductors  of  the  thumb. 

4.  That  abduction  of  the  little  finger  is  possible  (with  reference  to  the  axis  of  the 
hand),  this  abduction  is  very  slight. 

5.  That  there  is  no  actual  hyperkeratosis  whatsoever  in  the  distribution  of  the  ulnar, 
which  is  anesthetic. 

A,  Maximum  flexion  of  the  fingers.     Note  : 

1.  That  prominence  of  the  flexor  carpi  ulnaris  above  the  pisiform  persists. 

2.  That  the  phalanges  of  the  last  two  fingers  are  flexed  as  well  as  those  of  the  first 
two. 

3.  That  flexion  of  the  first  phalanx  is  far  more  pronounced  in  the  last  two  fingers 
than  in  the  first  two. 

c,  d,  e,f,  Muscular  contraction  in  voluntary  movements,  in  resistance  movements, 
and  by  electrical  stimulation. 

Black :  no  appreciable  voluntary  contraction,  no  contraction  in  any  of  the  muscles  to 
electrical  stimulation  of  the  nerve  above  the  injury  (diadermic  stimulation).  Total 
RD  in  all  these  muscles. 

Hatching:  voluntary  contraction  takes  place;  it  is  only  slightly  diminished.  Con- 
traction to  electrical  stimulation  of  the  nerve  ahove  the  lesion.  Partial  RD  (farad ic 
excitability  is  less  manifest  in  the  interossei  of  the  last  interspaces  than  in  those  of  the 
first).     The  hatchings  are  closer,  to  indicate  that  voluntary  contraction  is  less. 

Dotted :  slight  weakening  ;  electrical  hypo-excitability,  without  RD. 

g,  //,  Cutaneous  sensibility  to  pin-prick.     /',  Osseous  sensibility  to  tuning-fork. 

/,  Articular  sensibility  to  passive  attitudes. 

hi  black:  complete  cutaneous  and  osseous  anaesthesia  ;  attitudes  are  not  recognised. 
///  horizontal  hatching:  anesthesia  to  pain. 

In  oblique  hatching:  osseous  hypo-sesthesia  (the  hatching  is  closer,  to  indicate  that 
sensation  is  less,  compared  with  the  opposite  side). 

*  Figures  101  and  102  and  legends  are  taken  from  the  article  by  J.  Dejerine,  Mine.  Dejerine, 
and  J.  Mouzon,  Presse  Medicate,  No.  40,  30  August,  1  cj  1  5. 


ULNAR    NERVE 


161 


a,  Attitude  of  the  hand  at  rest.  />,  Maximum  flexion  of  the  fingers. 


c,  d,  e,J\  Voluntary  and  electrical  contractility  of  the  muscles. 


gi  h,  Cutaneous  sensibility  to  pin-pricking. 


i,  Osseous  sensibility         /,  Articular  sensibility 
to  tuning-fork.  to  passive  attitudes. 


1 1 


1 62  NERVE   WOUNDS 

Fig.  137. — Case  of  Corporal  Chev  ...  30  April,  1915,  71st  day  after  his  wound. 
Compression  of  external  surface  of  left  ulnar  nerve  in  the  upper  arm  (partial  lesion). 

Corporal  Chev  ...  of  the  228th  Infantry,  wounded  on  the  18th  Feb.,  1915,  at 
Suzanne  (Somme),  by  the  bursting  of  a  shell.  The  projectile  traversed  the  inner  region 
of  the  left  arm,  four  fingers1  breadths  below  the  armpit.  Suppuration  of  tract  and 
drainage.  Ulnar  paralysis  seems  to  have  been  immediate,  but  for  several  weeks  move- 
ment of  the  arm  was  rendered  almost  impossible  by  reason  of  the  pains  set  up  in  the 
last  two  fingers,  doubtless  connected  with  the  pulling  on  the  nerve.  These  pains  had 
almost  disappeared  at  the  time  the  wounded  man  entered  the  hospital. 

Operation,  17  May  (88th  day  after  the  wound),  by  M.  Gosset.  Ulnar  nerve  bent 
on  a  very  hard  fibrous  cord  which  strongly  compressed  its  external  surface,  and  was 
stretched  between  the  external  edge  of  the  biceps  and  the  outer  bend  of  the  biceps.  Re- 
section of  this  cord.  The  nerve  was  normal  in  calibre,  aspect  and  colour,  with  the 
exception  of  a  slight  swelling  and  hardening  (interstitial  sclerosis)  of  its  external  part. 

a,  Attitude  of  the  hand  at  rest  (disturbances  of  tone). 
Note  :   1.  That  the  hand,  in  its  entirety,  is  deviated  towards  the  radial  edge  (atony  of 
flexor  carpi  ulnaris). 

2.  That  there  is  no  trace  of  "ulnar  griffe."  On  the  other  hand,  the  flexion  folds  of 
the  phalanges  of  the  last  two  fingers  are  less  obvious  (the  tone  of  the  interossei  of  the 
last  two  outer  spaces  is  greater  than  that  of  the  corresponding  slips  of  the  flexor 
profundus). 

3.  That  atrophy  of  the  adductors  of  the  thumb,  at  the  thenar  eminence,  seems  more 
pronounced  than  atrophy  of  the  hypothenar  eminence. 

4.  That  abduction  of  the  little  finger  (as  regards  the  axis  of  the  hand)  is  very 
marked  ;  this  abduction  seems  connected,  on  the  one  hand,  with  the  favourable  tone  of 
the  muscles  of  the  hypothenar  eminence,  and,  on  the  other  hand,  with  the  tonic  action  of 
the  extensor  tendons,  whose  role  as  abductors  is  intensified  when  the  hand,  as  in  this 
case,  finds  itself  deviated  towards  the  radial  border. 

5.  The  considerable  hyperkeratosis  that  exists  throughout  the  entire  paresthetic 
region  of  the  ulnar  nerve,  and  which  extends  right  to  the  region  of  the  median. 

b,  c,  Maximum  flexion  of  fingers. 
Note  :   1.  That   projection  of  the  flexor  carpi  ulnaris  above  the  pisiform  is  quite 
absent. 

2.  That  there  is  no  flexion  of  the  last  phalanx  in  the  case  of  the  last  two  fingers, 
and  only  imperfect  flexion  in  the  case  of  the  middle  finger. 

3.  That  flexion  of  the  first  phalanx  of  the  fingers  is  effected  better  than  in  the  case 
of  Fig.  1 01,  and  also  better  in  the  latter  fingers  than  in  the  former  (the  outer  interossei 
are  more  weakened  than  the  inner  interossei). 

<!■>  e>f>g>  Muscular  contraction  in  voluntary  movements  and  movements  of  resistance, 
and  by  electrical  stimulation. 
Black :    no    appreciable  voluntary  contraction  ;    doubtful    contraction    to   electrical 
stimulation  of  the  nerve  above  the  lesion  5  partial  RD. 

Hatching :    voluntary  contraction  is  possible,  though   diminished.     These    muscles 
contract  to  electrical  stimulation  of  the  nerve  above  the  lesion  (diadermic  stimulation)  ; 
partial  RD.     (The  hatching  is  closer,  because  voluntary  contraction  is  less.) 
Dotted:  slight  weakening  ;  electrical  hypo-excitability,  without  RD. 

h,  Articular  sensibility  to  passive  positions  :  no  disturbance  whatsoever,     i.  Osseous 
sensibility  to  tuning  fork,    j,  k,  Cutaneous  sensibility  to  pin-prick. 
In  oblique  hatching  :  painful  hypo-a;sthesia  to  pin-prick  ;  slight  bony  hypo-xsthesia. 
In  oblique  cross-hatching :  paresthesia. 
In  oblique  dotted-hatching:  very  painful  paresthesia. 

Dotted:  painful  hyperesthesia,  strictly  so-called  (no  enlargement  of  Weber's  circles) 
osseous  hyperesthesia. 

A  comparison  of  Figs.  101  and  102  shows  that,  deep  in  the  ulnar  nerve  on  the  arm, 
the  general  arrangement  of  the  fasciculi  seems  to  be  as  follows  :  from  within  outwards, 
the  cutaneous  sensory  (dorsal  and  palmar)  branches  along  with  the  branches  to  the 
hypothenar  eminence — then  the  deep  branch  of  the  nerve,  the  branches  of  the  last 
interosseous  spaces  being  within,  those  of  the  last  spaces  further  without,  those  of  the 
adductors  of  the  thumb  still  further-  and  lastly,  on  the  outer  surface  of  the  nerve  the 
fasciculi  for  the  flexor  carpi  ulnaris,  and  for  the  flexor  profundus  (inner  slips). 


a.  Attitude  of  the  hand  at  rest. 


b,  c,  Maximum  movements  of  flexion  of  fingers. 


l^e->J,K,  Voluntary  and  electrical  contraction  of  muscles. 


h,  Articular  sensibility       i,  Osseous  sensibility 
to  passive  attitudes.  to  tuning-fork. 


/',  i\  Cutaneous  sensibility  to  pin-prick. 


164 


NERVE   WOUNDS 


DIAGNOSIS  OF   ULNAR   PARALYSIS 

Diagnosis  of  ulnar  paralysis  requires  little  more  than  the    indication 
of  a  few  causes  of  error. 


Fig.  138. 


Fig.  139. — False  ulnar  griff e  by  cicatricial  contraction  of  the  flexors  of  the  last  two 
fingers.  Relax  the  contracted  muscles,  flexing  the  fingers  on  the  hand  or  the  hand  on 
the  wrist,  to  obtain  reduction  of  griff e. 


ULNAR   NERVE  165 

1.  Note  the  frequent  absence  of  the  typical  ulnar  griffe,  which  may  be 
scarcely  perceptible. 

Nothing  is  easier  than  to  be  mistaken  regarding  paralysis  of  the  ulnar, 
and  perhaps  more  particularly  as  regards  complete  paralysis  through  lesion 
of  the  nerve  above  the  epitrochlea  ;  indeed,  it  is  in  this  case  that  griffe 
is  least  pronounced,  owing  to  paralysis  of  the  flexor  profundus. 

It  should  be  remembered  that  almost  all  movements  of  the  ulnar  may 
be  reproduced  by  substitutionary  movements.  True,  these  are  far  weaker, 
but  a  superficial  observation  might  lead  us  to  imagine  that  we  were  dealing 
with  simple  paresis  of  the  nerve.  Lateral  adduction  alone  of  the  fifth 
finger  cannot  be  substituted  ;  this  is  almost  the  only  movement  which  is 
absent  in  certain  cases. 

2.  Just  as  we  may  be  mistaken  in  ulnar  paralysis  so  may  we  regard  as 
an  ulnar  griffe  the  simple  cicatricial  contraction  of  the  flexors  of  the  last 
two  fingers. 

In  this  case,  indeed,  there  is  a  real  resisting  griffe,  apparently  inexten- 
sible,  and  therefore  reminding  one  of  the  fibrous  griffe  in  nerve  irritation. 

It  is  felt,  however,  when  employing  traction  in  order  to  straighten  the 
griffe,  that  the  resistance  is  in  the  fore-arm,  not  in  the  hand  ;  the  traction 
movements  raise  like  cords  the  contracted  muscles  and  draw  on  the  scar. 

Finally,  if  care  is  taken  to  flex  the  fingers  on  the  metacarpus,  or  the 
hand  on  the  fore-arm,  free  play  is  given  to  the  contracted  muscles  and  it 
is  noticed  that  the  griffe  is  completely  reduced,  without  deformity  of  the 
fingers. 

It  is  unnecessary  to  add  that  the  hypothenar  eminence  and  the  inter- 
ossei  show  no  sign  of  atrophy. 

3.  Finally,  we  must  insist  on  certain  contractions  appearing  in  the 
ulnar  distribution.  They  often  give  rise  to  appearances  which  might  be 
mistaken  for  ulnar  griffes  and  paralyses. 


CONTRACTIONS  RESULTING   FROM   SLIGHT   NEURITIS   OF 

THE  ULNAR 

Contractions  of  the  hand  constitute  a  very  special,  important  and 
interesting  chapter  in  the  study  of  irritations  of  the  ulnar. 

Indeed,  there  are  often  found,  following  slight  wounds  of  this  nerve, 
states  of  muscular  hypertonia  or  even  of  real  contraction,  to  which  we 
have  already  called  attention. 

Whilst  all  slightly  irritated  motor  nerves  seem  susceptible  of  producing 
analogous  syndromes,  the  ulnar  would  appear  to  produce  them  with  special 
frequency.  As  the  median  seems  to  respond  very  frequently  to  slight 
irritations  of  its  sensory  fibres,  producing  the  causalgic  syndrome,  so  the 
ulnar  seems  to  manifest  greater  susceptibility  of  its  motor  fibres  and  to 
react  readily  to  their  irritation,  producing  the  hypertonic  syndrome.     It  is 


1 66  NERVE   WOUNDS 

generally  a  case  of  direct  lesion  of  the  nerve,  sometimes  indirect  compres- 
sion or  lengthening  by  traction  ;  in  other  cases,  the  nerve  seems  irritated 
by  a  process  of  slight  ascending  neuritis. 

We  note  in  every  case  the  appearance  of  muscular  hypertonia, 
frequently  amounting  to  contraction,  and  immobilising  the  hand  in  a 
fixed  attitude. 

All  the  muscles  have  retained  their  normal  electrical  reactions,  but 
they  are  contracted.  Active  movements  are  impossible,  passive  move- 
ments are  difficult  and  meet  with  considerable  resistance  of  an  elastic  type 
which  is  non-fibrous  and  almost  always  painful.  As  a  rule,  the  pain  dis- 
appears as  soon  as  contraction  is  overcome  and  the  movement  carried  out  ; 
left  to  itself,  however,  the  hand,  either  immediately  or  more  slowly,  in  a 
few  minutes  or  in  a  few  hours,  regains  its  original  condition. 

One  might  pronounce  this  to  be  a  case  of  hysterical  contraction,  did 
not  the  attitude  of  the  hand  show  distinct  localisation  in  the  distribution 
of  the  ulnar ;  pain  in  the  nerve  under  pressure,  formication  caused  by 
percussion,  anaesthesia  or  hypo-assthesia  of  the  cutaneous  area,  vaso-motor, 
sweat  or  trophic  disturbances,  mechanical  and  often  electrical  hyper- 
excitability  of  the  contracted  muscles,  all  these  clearly  demonstrate  the 
irritative  origin  of  these  hypertonic  syndromes. 


Nothing  could  be  more  variable  than  the  contracted  attitudes  produced 
by  irritation  of  the  ulnar  ;  indeed,  the  different  muscles  supplied  by  this 
nerve  have  antagonistic  functions,  and  according  as  any  particular  group 
is  preponderant  we  find  altogether  different  attitudes.  Nor  must  it  be 
forgotten  that  contraction  becomes  fixed  and  intensified  by  immobilisation. 
Contraction  in  flexion,  for  instance,  becomes  contraction  in  extension,  if 
after  overcoming  it  we  immobilise  it  in  this  attitude.  We  may  con- 
sequently see  in  one  and  the  same  patient  different  attitudes  succeeding 
one  another.     The  main  types  we  will  now  review. 

Sometimes  we  have  contraction  of  the  muscles  of  the  hand,  producing 
the  "  accoucheur's  hand  "  type  described  by  Froment  and  Babinski.  The 
fingers  are  pressed  against  one  another  or  even  intercrossed  by  contraction 
of  the  palmar  interossei  ;  the  thumb  is  immobilised  by  the  adductors,  the 
little  finger  is  kept  in  a  state  of  forced  adduction. 

As  a  rule,  contraction  does  not  affect  the  thumb  and  is  even  at 
times  confined  to  the  hypothenar  eminence  ;  the  little  finger  is  in  forced 
adduction  and  obliquely  crosses  the  anterior  surface  of  the  other  fingers. 

In  all  cases,  there  is  immobilisation  of  the  fingers  in  extension  by  the 
action  of  the  interossei  on  the  second  and  third  phalanges. 

Wc  also  find  that  certain  cases  in  which  it  is  impossible  to  flex  the 
fingers,  particularly  the  last  two  fingers,  are  due  to  contraction  of 
the  interossei. 

Immobilised  when  extended,  these  fingers  do  not  offer  to  passive  flexion 


ULNAR   NERVE  167 

the   fibrous  and  articular   resistance  which   we   find    in    certain   cases  of 


Fig.  140. — Contraction  limited  to  the  hypothenal  eminence  with  slight  contraction  of 
the  palmar  interossei.  Ulnar  hypo-xsthesia.  Hypo-xsthesia  of  the  internal  cutaneous. 
Pain  and  formication  in  the  nerve  as  far  as  the  armpit.  Very  pronounced  trophic 
change  in  the  little  finger  nail.  Compression  of  the  ulnar  and  ot  the  internal 
cutaneous  at  the  level  of  the  armpit,  or  slight  traction  on  the  lower  roots  ot  the  brachial 
plexus. 


Fig.  141. — Contraction  with  extension  ot  two  fingers;  maximum  ot  voluntary  move- 
ments. The  fingers  may  very  readily  be  flexed,  but  they  immediately  resume  their 
original  attitude  as  though  moved  by  a  spring.  Lesion  of  the  ulnar  above  the 
epitrochlea.  Ulnar  hypo-xsthesia  with  hypo-xsthesia  of  the  internal  cutaneous. 
Originally  the  patient  had  contraction  in  flexion  of  the  last  two  fingers  ;  after  opining 
of  the  hand  and  immobilisation  in  extension  for  several  weeks,  contraction  in 
extension  occurred. 


neuritis.     Voluntary  flexion  of  the  first  phalanx  is  possible  and  sometimes 


i68 


NERVE   WOUNDS 


even  exists  permanently,  thus  showing  full  movement  of  the  interossei. 
Passive  flexion  of  the  last  two  phalanges  is  possible  and  even  tolerably 
easy,  affording  the  impression  of  elastic  resistance,  but  left  to  themselves 
the  fingers  at  once  resume  their  initial  attitude  as  though  moved  by  a 
spring,  or  else  they  regain  it  slowly  after  a  few  minutes. 

In  other  cases  we  find  contraction  of  the  hand  along  with  flexion  of 
the  fingers  ;  of  this  two  typical  varieties  may  be  described.  Sometimes 
we  have  flexion  of  all  the  fingers  by  the  interossei ;  flexion  then  almost 
exclusively  affects  the  first  phalanx  ;  the  second  and  third  are  but 
moderately  flexed.  In  these  cases  there  is  often  more  or  less  pronounced 
contraction  of  the  palmar  aponeurosis,  the  existence  of  which  intensifies 


l 


1 


Fig.  142. — Contraction  of  the  hand  in  flexion.  Slight  wound  of  the  ulnar  in  the 
middle  part  of  the  arm.  Liberation  of  nerve  two  months  after  the  wound.  Con- 
traction, which  appeared  some  weeks  after  the  wound,  has  become  exaggerated  after 
operation.  Complete  ulnar  anaesthesia.  Slight  hypo-aesthesia  of  the  median.  Con- 
traction of  the  palmar  aponeurosis.  Passive  extension  of  the  hand  is  possible  though 
painful  ;  consequently  the  hand  remains  extended,  voluntary  flexion  impossible  ;  in  a 
few  hours  it  resumes  its  original  flexed  attitude. 

flexion  of  the  fingers  as  well  as  resistance  to  passive  movements  ;  it  clearly 
indicates  irritation  of  the  nerve  trunk. 

Soon  after  we  note  flexion  of  the  last  two  fingers  on  the  hand  through 
contraction  of  the  flexor  profundus,  producing  an  attitude  which  re- 
sembles, though  somewhat  exaggerated,  that  of  ulnar  griff e  in  paralysis 
accompanied  by  neuritis. 

Whilst  in  all  these  contractions  there  undoubtedly  exists  a  motor  nerve 
irritation  which  causes  them,  still  this  is  not  the  main  factor,  perhaps  in 
most  cases  it  is  not  even  the  most  important  factor. 

As  a  rule,  this  irritation  acts  only  by  causing  a  sort  of  muscular 
hypertonia,  an  actual  predisposition  to  contraction.     What  more  than  all 


ULNAR    NERVE 


169 


else  favours,  maintains,  and  intensifies  this  ncuritic  contraction  in  almost 
every  case,  is  immobilisation.  From  the  time  when  they  are  slowly, 
patiently,  and  regularly  mobilised,  these  contractions  diminish  and  finally 
disappear. 

We  are  justified  in  thinking  that  they  would  not  exist  for  the  most 
part  if  we  had  practised  this  daily  mobilisation  from  the  outset,  and  if 
the  patient  had  not  shown  a  certain  amount  of  indifference,  or  even 
willingness,  in  allowing  contraction  to  take  place. 

This  is  proved  by  the  habitual  preservation  of  the  movements  of  the 
thumb  ;  even  when  there  is  contraction  of  the  interossei,  the  adductors  of 
the  thumb  almost  always  escape  contraction  and  retain  their  movements 


Fig.  14.3. — Flexion  or  the  last  two  fingers 
may  be  thought  to  be  due  to  muscular 
fore-arm  in  its  inner  part.  All  the  same 
complete  extension  may  be  obtained  w 
reproduced  several  minutes  afterwards, 
middle  part  of  the  arm,  hypo-aesthesia  of 
of  the  adductors  of  the  thumb,  cyanosis 
the  ulnar  part  or  the  hand,  point  to  invol 
by  a  process  of  ascending  neuritis. 


by  contraction  of  the  flexors.     The  attitude 

contraction,  for  the  wound  has  affected  the 

,  there  is  no  cicatricial  muscular  contraction  ; 

without    great    resistance,  and   the  attitude    is 

Pain    in   the  ulnar  when   pressed    on    in   the 

its  cutaneous  area,  simultaneous  contraction 

of  the  little  finger,  profuse  sweats  noticed   in 

vement  of  the  ulnar  nerve,  probably  irritated 


which  the  patient  finds  indispensable  in  using  his  hand  :  out  of  fifteen 
cases  of  contraction  in  the  region  of  the  ulnar,  only  twice  have  we  found 
immobilisation  of  the  thumb  by  the  contracted  adductors. 

It  must  be  remembered  that  these  ncuritic  contractions  are  almost 
always  partially  functional  ;  great  care  must  be  taken  to  prevent  their 
appearance  or  persistence  by  practising  mobilisation  on  the  patient  at  an 
early  stage  and  above  all  by  requiring  that  he  himself  should  do  everything 
possible. 

Once  contraction  has  been  established,  massage,  hot  baths,  mobilisation 
under  warm  water,  the  faradic  bath  with  metronome  rhythm,  have  in- 
variably given  excellent  results. 


CHAPTER   VIII 
MEDIAN  NERVE 

ANATOMY 

The   median   nerve  originates   in   the   brachial   plexus   from  two  heads  : 
the   outer  head,  coming  from   the    outer  cord  along   with  the  musculo- 


Lesser  int.  cut. 


Median 


Brachial  artery 


Musculo-spiral 
Ext.  cut.  br. 

Musculo-spiral 


Ulnar 


Biceps 


Fig.  144. — Deep  nerves  of  the  arm  (after  Hirschfeld  modified). 
Anterior  aspect. 


cutaneous,  brings  to  it  fibres  of  the  sixth  and  seventh  cervical  roots  ;  the 


MEDIAN    NERVE 


171 


inner   head,  coming  from  the    inner   cord    trunk,   along  with   the   ulnar, 
supplies  it  with  fibres  from  the  eighth  cervical  and  of  the  first  dorsal. 

The  median  nerve  descends  into  the  armpit  in  front  of  the  axillary 
artery.  It  proceeds  along  the  inner  side  of  the  arm,  lying  against  the 
inner  side  of  the  biceps,  in  front  of  and  outside  the  brachial  artery,  which, 


Met!. 


Musculo-spiral 

Post,  branch 

Sup.  long. 
Flex,  sublim.  - 

Ext.  carpi  rati,  longior  —  \Cy 
Musculo-spiral  (ant.  branch) 


Pron.  quadratus  - 


Thenar  eminence 


Pronat.  radii  teres 

Flex,  carpi  ulnar 

Ulnar  N. 

Flex.  prof. 

Anterior  interosseous 


Ulnar  (dorsal  branch) 
Deep  branch 
Superficial  branch 


Fig.  145. — Deepinerves  of  the  tore-arm  and  nerves  of  the  hand  (after  Hirschteld). 

at  its  lower  part,  crosses  its  deep  surface  and  becomes  external  to  it.  It 
proceeds  in  front  of  and  outside  the  ulnar,  which  is  closely  united  with  it 
as  far  as  the  lower  third  of  the  arm. 

At  this  level,  the  ulnar  separates  itself  from  the  median    to  reach  the 
epitrochlean  groove  which  is  behind,  whilst  the  median  slightly  inclines 


172  NERVE   WOUNDS 

outwards  in  order  to  draw  nearer  to  the  middle  line  of  the  upper  limb  at 
the  bend  of  the  elbow. 

In  the  fore-arm,  it  proceeds  between  the  two  heads  of  the  pronator 
radii  teres,  and  disappears  beneath  the  superficial  flexor.  It  descends  in 
the  middle  line  resting  on  the  flexor  profundus,  covered  by  the  superficial 
flexor.  Below  the  fleshy  body  of  this  muscle,  at  the  lower  part  of  the 
fore-arm,  where  it  becomes  superficial,  it  appears  between  the  tendons  of 
the  flexor  indicis  and  the  tendon  of  the  flexor  carpi  radialis. 

It  passes  on  to  the  wrist  under  the  annular  ligament  of  the  carpus  ; 
occupies  the  anterior  compartment  of  the  radio-carpal  canal,  and  divides 
into  its  terminal  branches  :  the  inner  trunk  and  the  outer  trunk. 


Motor  Branches 

The  median  nerve  does  not  supply  any  branch  whatsoever  to  the 
arm,  except  a  few  twigs  for  the  brachial  artery  and  the  articulation  of  the 
elbow. 

I. — All  the  branches  of  the  median  in  the  fore-arm  are  exclusively 
motor,  except  the  palmar  cutaneous  branch,  which  appears  a  little  above 
the  wrist  and  is  destined  for  the  hand. 

1.  Upper  nerve  to  the  pronator  radii  teres. 

2.  Nerves  to  the  superficial  muscles  of  the  fore-arm,  destined  : 
For  the  pronator  radii  teres  (lower  nerve). 

For  the  flexor  carpi  radialis  and  palmaris  longus. 

For  the  superficial  flexor. 

All  these  branches  originate  close  to  the  elbow  (Cruveilhier)  ;  but 
some  accessory  twigs  also  become  detached  lower  down,  particularly  for 
the  flexor  of  the  index. 

3.  Nerves  of  the  deep  layer,  comprising  : 

A  branch  which  supplies  the  two  external  heads  of  the  flexor  profundus  ; 

A  branch  destined  for  the  flexor  of  the  thumb ; 

A  branch  which  descends,  under  the  name  of  anterior  interosseous 
nerve,  in  front  of  the  interosseous  ligament,  supplies  the  pronator  quadratus 
and  reaches  the  proximate  articulations  of  the  carpus,  where  it  ends. 

II. — In  the  hand,  the  median  nerve  supplies  : 

1.  The  muscles  of  the  thenar  eminence  by  three  branches,  origi- 
nating in  its  external  branch  and  destined  : 

For  the  abductor  of  the  thumb  ; 

For  the  opponens ; 

For  the  flexor  brevis. 

The  median  does  not  supply  the  adductors  of  the  thumb,  which  the 
ulnar  supplies  in  the  same  way  as  the  interossei. 

It  also  supplies  only  the  superficial  part  of  the  flexor  brevis  ;  the  deep 
head  is  supplied,  partially  at  least,  by  the  ulnar. 


MEDIAN    NERVE 


173 


2.  The  first  two  lumbricales,  by  branches  originating  in  its  inner 
branch.     Occasionally  it  also  supplies  the  third  lumbrical. 

Sensory  Branches 

Whereas  in  the  fore-arm  the  median  nerve  is  exclusively  motor,  in  the 
hand  it  is  mostly  sensory. 

1.  Palmar  cutaneous  branch. — This  collateral  branch  appears  a  little 
above  the  wrist  and  disappears  in  the  skin  of  the  thenar  eminence  and  of 


Musculo-spiral  N.  (ext.  br. 
Musculo-cutaneous  N.  ,, 


Musculocutaneous  N.  (ant.  br 
Musculo-cutaneous  N.  (post,  br.) 

Musculo-cutaneous  N.  (ant.  br.) 


Anastom.  muse.  cut.  and  musc.-spiral 


Collat.  thumb 


-  Int.  cut.  nerve  (anter.  br.) 
_  Int.  cut.  nerve  (anter.  branch,  ext. 
twig) 


Inter,  cut.  nerve,  (anter.  branch, 
inter,  twig) 


Anastom.  cutan.  branch  and  ulnar 


Median  N.  (palm,  cutan.  branch) 


Col.  digital 


Anterior  aspect. 
Fig.  146.— Cutaneous  nerves  of  fore-arm  and  hand.     (After  Sappey.) 

the  palm  of  the  hand,  which  it  supplies  as  far  as  the  middle  palmar  crease 
1  2.  The  external  terminal  branch  of  the  median,  from  which  also 
originate  the  motor  branches  of  the  thenar  eminence,  supplies  : 

The  external  digital  collateral  nerve  of  the  thumb  ; 

The  internal  digital  collateral  nerve  of  the  thumb  ; 

The  external  digital  collateral  of  the  index. 

3.  The  internal  terminal  branch  supplies  through  the  inter-digital 
nerves  of  the  second  and  the  third  space  : 


i74  NERVE   WOUNDS 

The  internal  digital  collateral  of  the  index  and  the  external  collateral 
of  the  middle  finger  ; 

The  internal  collateral  of  the  middle  finger  and  the  external  collateral 
of  the  ring-finger. 

All  the  digital  collaterals  of  the  fingers,  except  those  of  the  thumb, 
successively  send  out  a  dorsal  branch  for  the  second  phalanx  and  one  for 
the  third  phalanx,  so  that,  in  the  case  both  of  the  median  and  of  the  ulnar, 
the  dorsal  surface  of  the  last  two  phalanges  is  supplied  by  the  palmar 
nerves  :  the  thumb  and  the  fifth  finger  alone  form  an  exception  to  this  rule. 


Anastomotic  Branch 

It  is  useless  to  enumerate  the  terminal  anastomoses  of  the  median 
along  with  the  musculo-spiral,  the  ulnar,  or  the  musculocutaneous. 
Unlike  those  of  other  nerves  they  have  no  interest  for  the  clinician.  This 
is  not  so  in  the  case  of  the  anastomosis  supplied  to  the  median  by  the 
musculocutaneous,  at  the  middle  of  the  arm.  Probably  it  supplies  the 
median  nerve  with  the  motor  fibres  coming  from  the  sixth  and  seventh 
cervical  roots  ;  it  is  the  more  developed  in  proportion  as  the  external  root 
of  the  median  is  slighter  ;  and  so  its  persistence,  in  the  complete  sections 
of  the  median  above  it,  would  explain  the  possible  preservation  of  some 
nerve  fibres  supplying  the  flexor  carpi  radialis  and  the  pronator  radii  teres. 

The  median  also  receives  in  the  arm  and  the  fore-arm  some  slight 
anastomotic  twigs  from  the  ulnar  nerve,  capable  of  supplying  occasionally 
substitutionary  fibres  to  the  flexor  profundus  of  the  middle  finger. 


MEDIAN   NERVE 


'75 


PHYSIOLOGY 


147. 


Fig. 


Motor  Syndrome 

I. — The  median  nerve  in  the  fore-arm  is  exclusively  motor. 
It  controls  : 

1.  Pronation  by  the  pronator  quad  rat  us  and  the  pronator  radii  teres 
Babinski  found  that,  in  paralysis  of  the 

median,  electrical  stimulation  of  the  biceps 
produces  supination  more  pronounced  than 
in  the  normal  state  as  a  result  of  lack  of 
antagonism  of  the  pronator  radii  teres. 

2.  Flexion  of  hand  on  fore-arm  by  the 
flexor  carpi  radialis,  etc. 

Nevertheless,  in  paralysis  of  the  median, 
slight  flexion  of  the  hand  is  still  possible 
by  the  flexor  carpi  ulnaris,  and  the  synergic 
contraction  of  the  supinator  longus  and  of 
the  extensor  ossis  metacarpi  pollicis. 

3.  Flexion  of  the  fingers  by  the  super- 
ficial flexor  and  the  flexor  profundus.  In 
spite  of  paralysis  of  the  median,  flexion  of 
the  last  two  fingers  remains  possible  by 
means  of  slips  of  the  flexor  profundus  sup- 
plied by  the  ulnar. 

The  fingers  which  cannot  be  flexed   in 

paralysis  of  the  median  are  the  thumb,  the 

index  and  middle  finger. 

Flexion     is    absent    in    the     last    two 

phalanges  only  ;  the  ulnar   being  capable, 

through  the  interossei, 
of  flexing  the  first  pha- 
langes of  middle  finger 
and  index  on  the  meta- 
carpus. 

On  the  other  hand, 
in  spite  of  the  typical 
anatomical  descriptions, 
the  middle  finger  can 
frequently  be  flexed  in 
paralysis  of  the  median. 
This  is  not  only  owing 
to  the  aponeurotic  fibres 
which  unite  the  flexors 
of  the  middle  finger  to 

those  of  the  ring-finger,  but  to  actual  muscular  contraction.     It  must  of 


Muscles  supplied  by  the  median 
in  the  fore-arm. 

Fig.  147. — Superficial  layer.  Pro- 
nator radii  teres.  Flexor  carpi 
radialis.  Palmaris  longus. 
Superficial  flexor. 

Fig.  148. — Deep  layer.  Pronator 
quadratus.  The  two  external 
fasciculi  of  the  flexor  profundus. 
Flexor  of  the  thumb. 


149. — Superficial  layer.         Fig.  150. — Deep  layer. 

Muscles  supplied  by  the  median  in  the  hand. 

Figs.    149    and    150. — Abductor   pollicis.      Opponens, 

Flexor  brevis  pollicis.     The  first  two  lumbricales. 


176 


NERVE   WOUNDS 


necessity  be  admitted  that  the  flexor  profundus  of  the  middle  finger  is 
very  often  supplied,  partially  at  least,  by  the  ulnar. 

II. — In  the  hand  the  median  nerve  supplies  all  the  muscles  of  the 
thenar  eminence,  except  the  adductors  and  the  deep  head  of  the  flexor 
brevis. 

Paralysis  of  the  median  is  mainly  characterised  by  loss  of  the  opposition 
and  flexion  movements  of  the  thumb,  whilst  adduction  persists. 

The   patient  can   grasp  an   object  firmly  and    press   it  between   the 

first  phalanx  of  the  thumb  and  the  base 
of  the  index,  but  he  cannot  pinch  it 
between  the  end  of  the  thumb  and  the  last 
phalanxes  of  the  index  ;  still  less  between  the 
thumb  and  the  end  of  the  other  fingers. 

On  the  other  hand,  the  thumb  is  capable 
of  slight  external  rotation. 

Nevertheless,  energetic  contraction  of  the 
adductors  enables  it  frequently  to  move  to 
the  ulnar  edge  of  the  hand,  by  crawling, 
so  to  speak,  against  the  base  of  the  fingers. 
This  is  the  pseudo-opposition  of  the  thumb 
described  by  H.  Claude,  facilitated  by  lack 
of  tone  in  the  other  thenar  muscles  and  by 
articular  laxity. 

The  flexion  movements  of  the  thumb 
are    completely    suppressed    (long  and   short 

Fig.  151.— Pseudo-opposition  in  flexors)  ;  still,  a  slight  flexion  movement  of 
paralysis  of  the  median.     The       ,  111  •  ■        n  -i  1      1 

thumb  in   its  course  inwards  the  second  phalanx  is  occasionally  possible,  by 

approaches  the  little    finger ;  means  of  the  deep  head  of  the  flexor  brevis. 
skimming    the    base    of    the  The    me(Han   alsQ   supplies    in    the   hand 

ringers.    Then  the  little  ringer  ,        rr 

is  bent  inwards  to  reach  the  the    first    two    lumbricales,  but    paralysis   of 

extremity  of  the  pulp  of  the     these    muscles    is  fully   compensated    for  by 

thumb.     (Claude,  Dumas,  and     .  .  r      .         .  . 

Porack,  Presse  Med.,  10  June,     integrity    of    the     interossei    and    causes    no 

1915.)  motor  disturbance  whatsoever. 


Sensory  Syndrome 

The  sensory  region  of  the  median  comprises  : 

1.  The    external    part    of   the    palm    of  the    hand,    though    without 
reaching  the  outer  side  of  the  thumb  ; 

2.  The    palmar   surface    of  thumb,    index    and    middle    finger :    the 
external  half  of  the  ring-finger  ; 

3.  The  dorsal  surface  of  the  second  and  third   phalanges  of  the  index 
and  the  middle,  and  the  external  half  of  the  ring-finger. 

In  the  median,  however,  as  in  the  ulnar,  total  anaesthesia  is  usually 


MEDIAN    NERVE 


177 


confined  to  a  portion  only  of  this  region,  almost  always  to  the  index  ;  it 
gradually  becomes  less  pronounced  as  we  approach  the  regions  of  the  ulnar 
and  the  radial. 


Figs.  152  and  153. — Anatomical  region  ot  the  median. 


Figs.  154  and  155. — Usual  topography  ot"  sensory  disturbances  of  tin  median.  Three 
diagrammatic  zones:  complete  anesthesia,  pronounced  hypo-;isthesia,  and  slight 
hypo-;esthesia. 


Trophic  Syndrome 

Trophic  disturbances  of  neuritis  of  the  median,  affect  the  palm  of  the 
hand  far  less  than  do  those  of  the  ulnar;  they  are  confined  chieflv  to  the 

12 


178  NERVE   WOUNDS 

fingers,  particularly  the  index  and  the  middle  finger  ;  they  affect  the  thumb 
to  a  less  degree  and  the  ring-finger  but  slightly.  They  act  mainly  on  the 
second  and  third  phalanges  as  well  as  on  the  nails  of  these  fingers,  the 
deformities  of  which  are  obvious  and  persistent. 

Apart  from  the  various  neuritic  disturbances  we  shall  study  later  on, 
we  may  note  in  simple  lesions  of  the  median,  the  cyanosis  and  redness 
of  the  innervated  fingers,  chiefly  the  index  ;  dryness  of  the  skin,  or,  on 
the  other  hand,  profuse  sweats  in  the  cutaneous  region  of  the  nerve,  also 
a  tendency  to  chilblains. 

Finally,  in  very  rare  cases,  we  may  note  the  appearance,  at  the  end  of 
the  fingers,  of  ecchymoses,  or  occasionally  of  small  ulcers,  caused  by  various 
mechanical  or  chemical  irritants. 

Muscular  atrophy  in  cases  of  paralysis  of  the  median  is  shown  mainly 
by  the  flattening  of  the  lower  part  of  the  fore-arm  following  atrophy  of 
the  pronator  quadratus. 


CLINICAL   FORMS   OF   LESIONS   OF  THE   MEDIAN   NERVE 

In  the  case  of  the  median,  even  more  than  of  the  ulnar,  it  is  not  easy  to 
differentiate  between  complete  interruption  and  simple  compression. 

Muscular  hypotonia  is  difficult  to  establish  ;  muscular  atrophy  of  the 
epitrochlear  and  thenar  muscles  is  more  rapid  and  pronounced  in  nerve 
interruptions,  but  sometimes  it  is  not  easy  to  judge,  by  reason  of  the 
preservation  of  the  flexor  carpi  ulnaris  and  of  the  internal  fasciculi  of  the 
flexor  profundus.  The  main  signs  of  interruption  are  the  early  appear- 
ance and  the  intensity  of  the  electrical  disturbances,  the  constancy  of 
anaesthesia  and  the  fixity  of  formication  which  is  found  at  the  level  of  the 
lesion. 

We  will  study  in  succession  : 

1.  Paralysis  of  the  median  above  the  epitrochlear  muscles  ; 

2.  Lesions  of  the  median  below  the  epitrochlear  muscles  ; 

3.  Dissociated  paralysis  of  the  median. 

4.  Neuritis  of  the  median. 

5.  Causalgia  of  the  median. 


I.-COMPLETE   PARALYSIS   OF  THE   MEDIAN    IN   THE   ARM 
ABOVE  THE    EPITROCHLEAR   MUSCLES 

Paralysis  of  the  median  is  not  shown  when  at  rest  by  any  special 
attitude.  It  is  revealed  solely  by  movement.  Pronation  is  impossible, 
however  little  resistance  is  offered  to  it ;  flexion  of  the  hand  on  the  wrist, 
which  is  very  feeble,  occurs  only  by  means  of  the  flexor  carpi  ulnaris  ; 
flexion    of  thumb,  index  and  middle  finger  is    impossible  ;   they  remain 


MEDIAN    NERVE 


*79 


extended  if  the  patient  tries  to  shut  his  hand,  whereas  the  last  two  fingers 
are  strongly  flexed  by  the  flexor  profundus  alone. 


Fi<;.  156. — Paralysis  of  the  median  nerve.     Complete  interruption  above  the 
epitrochlea.     Maximum  flexion  of  the  fingers. 

We  must,  however,  qualify  some  of  these  statements. 
On    the    one  hand,  the  middle    finger  may  often   be  slightly  flexed, 
being  affected  by  movement  of  the  ring-finger,  on  account  of  the  apo- 


FlG.  157. — Complete  paralysis  of  the  median   nerve  (resection  and  suture  at  the  middle 

third  of  the  arm).  The  interossei  are  capable  of  flexing  the  rirst  phalanx.  Flexion  ol 
the  last  two,  however,  is  impossible.  (In  this  case,  flexion  of  the  middle  is  possible,  by 
the  flexor  profundus,  which  is  sometimes  supplied  by  the  ulnar.) 

neurotic  slip  which  unites  their  extensor  tendons  on  the  dorsal  surface  of 
the  hand.  It  frequently  happens  that  flexion  of  the  middle  finger  is  almost 
complete  when  the  ulnar  supplies  a  branch  to  its  flexor  profundus. 


180  NERVE   WOUNDS 

On  the   other    hand,    the    interossei    are    capable    of  flexing  the  first 


Figs.  158  and  159. — Complete  paralysis  of  the  median  nerve.     Impossible 
to  flex  the  index  finger. 

phalanx  of  index  and  middle  finger  on  the  metacarpus,  but  the  last  two 

phalanges  remain  extended. 
It  is  easy  to  eliminate 
the  cause  of  error  produced 
by  the  action  of  the  inter- 
ossei and  to  show  that  flexion 
of  the  second  and  third 
phalanges  is  impossible  by 
requesting  the  patient  to 
intertwine  the  fingers  of 
both  hands  and  then  to  close 
them.  It  is  noticed  that 
the  index  finger  and  the 
thumb  remain  extended, 
that  flexion  of  the  middle 
finger  is  slight,  whereas  the 
last  two  fingers  can  be  flexed 
strongly.     (Pitres.) 

Again,  if  the  patient  is 
ordered  to  flex  his  hand  on 
his  wrist  and  his  fingers  on 
his  hand,  we  notice  exten- 
sion of  the  index  finger; 
this  would  seem  to  be  an 
irrefutable  sign  of  paralysis 


Fig.  160.— Paralysis  of"  the  median  (first  sign).  On 
the  left  side,  the  patient  cannot  bring  the  thumb 
in  front  of  the  middle  finger  as  on  the  right  side. 
(Claude,  Dumas,  and  Porack,  Presse  Med.,  10 
June,  1 9 15.) 


of  the  median.     (M.  and  Mine.  Dejerine.) 

Even  more  simply  we  may  firmly  fix  the  first  phalanx  of  the  index 


MEDIAN   NERVE 


1N1 


finger  and  ask  the  patient  to  flex  the  others  ;  alternatively,  his  hand  resting 
flat  on  a  table,  the  patient  is  asked  to  scratch  the  table  with  the  nail  of  the 
index  finger.     (Pitres  and  Testut.) 

Finally,  the  thumb  has  lost  all  its  power  of  flexion  and  opposition.  If 
the  patient  is  ordered  to  close  his  fist,  it  is  found  that  the  thumb  remains 
extended  and  cleaves  to  the  index  finger  instead  of  being  flexed  in 
opposition  in  front  of  the  other  fingers  (first  sign).     (H.  Claude.) 

There  may  sometimes  be  observed  manifest  dissociation  in  paralysis  of 
the  epitrochlear  muscles  ;  the  pronator  radii  teres,  the  flexor  carpi  radialis, 
and  the  palmaris  longus  have  partially  retained  their  movements  and  still 


FlG.  i 6 i. —Dissociated  paralysis  of  the  median.  Integrity  of  the  pronator  radii  teres, 
the  flexor  carpi  radialis,  and  the  palmaris  longus,  which  become  prominent  at  the 
wrist. 


preserve  slight  faradic  contractility,  whilst  the  flexors  are  paralysed.     This 
dissociation  may  be  found  in  three  forms. 

1.  As  the  result  of  lesion  of  the  nerve  at  the  bend  of  the  elbow,  below 
the  twigs  destined  for  the  pronator  radii  teres,  the  flexor  carpi  radialis  and 
the  palmaris  longus. 

2.  From  lesion  of  the  nerve  at  the  level  of  the  arm,  giving  rise  to  a 
dissociated  syndrome.  We  have  observed  this  several  times,  but  it  cannot 
be  affirmed  that  lesion  of  the  nerve  is  partial  in  all  these  cases.  Indeed  it 
may  be  remembered  that  the  anastomosis  coming  from  the  musculo- 
cutaneous brings  fibres  of  the  fifth  and  sixth  cervicals  to  the  median,  most 
of  these  fibres,  actual  aberrant  fibres  of  the  external  root  of  the  median, 
seem  destined  for  the  pronator  radii  teres  and  the  flexor  carpi  radialis, 
indeed  we  shall  see  (brachial  plexus)  that  the  external  and  superior  root  ol 
the  median  evidently  to  a  large  extent  supplies  the  pronator  radii  teres,  the 
flexor  carpi  radialis,  and  the  palmaris  longus. 


182 


NERVE   WOUNDS 


3.  This  dissociation  is  also  noted.in  the  course  of  progressive  regenera- 
tion of  the  nerve  ;  the  flexor  carpi  radialis,  the  palmaris  longus,  and  the 
pronator  radii  teres  regain  their  movements  before  the  other  flexors. 


II.— PARALYSIS   OF  THE   MEDIAN    IN   THE   FORE-ARM    BELOW 
THE   EPITROCHLEAR   MUSCLES 

Lesion  of  the  median  in  the  fore-arm  is  indicated  solely  by  paralysis  of 
the  thenar  eminence  and  by  anaesthesia  of  the  hand. 

These  disturbances  are  exactly  similar  to  those  found  in  total  paralysis 
of  the  median  ;  still,  it  is  well  to  study  paralysis  of  the  thenar  muscles  a 
little  more  closely,  and  to  compare  it  with  ulnar  paralysis. 


Fig.  162. — Atrophy  of  the  thenar  eminence  in  paralysis  of  the  median. 

If  paralysis  is  of  long  standing,  atrophy  of  the  thenar  eminence  is  very 
obvious,  but  the  paralysis  is  chiefly  shown  by  atrophy  of  the  abductor  and 
of  the  opponens  ;  it  induces  flattening  of  the  thenar  eminence  ;  a  flat  area 
or  even  a  depression  running  parallel  to  the  first  metacarpal,  replaces  the 
normal  projection.  This  atrophy  is  superficial  ;  it  is  not,  as  in  ulnar 
paralysis,  atrophy  of  the  deep  muscular  layers  (adductors  of  the  thumb  and 
deep  head  of  the  flexor  brevis).  Owing  to  integrity  of  the  flexor  longus 
pollicis,  flexion  of  the  thumb  is  not  abolished. 

The  only  movement  which  is  really  absent  is  that  of  opposition  ;  still 
it  is  sometimes  difficult  to  discover  this.  Indeed,  if  the  patient  is  asked  to 
touch  with  the  extremity  of  the  flexed  thumb  the  extremity  (if  sonic  other 
finger,  it  is  found  that  the  movement  is  possible  ;   this  is  not  done,  all  the 


MEDIAN    NERVE  183 

same,  by  frankly  setting  the  one  against  the  other,  it  is  effected  by  flexion 
of  the  thumb  in  the  hand  and  flexion  of  the  fingers  over  its  extremity  ; 
thumb  and  fingers  no  longer  meet  at  the  pulp,  as  in  normal  opposition,  but 
on  their  dorsal  or  lateral  side  ;  it  is  a  case  of  pseudo-opposition. 

Finally,  although  the  flexors  are  entirely  retained,  we  must  here  note 


Fig.  163.  Fig.  16+. 

Fig.  163. —  Normal   opposition  in  a  healthy  subject.     The  fingers  are  completely  and 

really  opposed  ;  rotation  of  the  thumb  is  complete. 
Fig.  164. — Pseudo-opposition   in  a  case  of  section  of  the  median  at  the  wrist.     The 

ringers  are  opposed  at  their  sides.     The  thumb  is  flexed  by  its  own  flexor,  supplied  in 

the  fore-arm,  far  above  the  wound. 

the  frequency  of  their  functional  paralysis,  a  pseudo-paralysis  caused  by 
ana-sthesia  of  the  hand  :  no  longer  feeling  his  fingers,  the  patient  thinks 
that  they  are  paralysed  and  does  not  even  attempt  to  use  them.  We  shall 
return  to  this  point  when  we  discuss  diagnosis. 


III.— DISSOCIATED  PARALYSES   OF   THE  MEDIAN 

The  median,  like  the  ulnar,  may  show  partial  lesions  and  dissociated 
paralyses. 

We  have  mentioned  the  relative  preservation  of  the  pronator  radii 
teres,  the  flexor  carpi  radialis,  and  the  palmaris  longus  sometimes  found  even 
in  certain  complete  interruptions  of  the  nerve  in  the  upper  part  of  the  arm  . 
possibly  in  these  cases  the  motor  fibres  originate  in  the  anastomosis  of  the 
musculo-cutaneous.  All  the  same,  more  complete  dissociations  may  be 
found. 

In  certain  cases,  for  instance,  there  is  found  to  be  complete  paralysis  of 


1 84 


NERVE   WOUNDS 


the  flexors  supplied  by  the  median  ;  flexion  of  the  index  finger  is  impossible  ; 
flexion  of  the  other  fingers  takes  place  solely  through  the  fasciculi  of  the 
flexor  profundus  which  is  supplied  by  the  ulnar.  The  pronator  radii  teres, 
however,  the  flexor  carpi  radialis,  the  muscles  of  the  thenar  eminence,  and, 
above  all,  the  opponens  have  retained  their  movements  ;  the  flexor  longus 
pollicis  is  weakened  but  not  wholly  paralysed. 

In  these  cases,  the  lesion  affects  the  inner  part  of  the  nerve. 

We  have  noted  three  cases  of  this  dissociated  form  ;  the  first  two  were 


Fig.  165.  Fig.  166. 

Fig.  165. — Dissociated  paralysis  of  the  median  nerve.     Paralysis  of  the  flexors.    Integrity 

of  the  flexor  carpi  radialis,  of  the  palmaris  longus,  of  the  pronator  radii  teres,  and  of 

the  opponens.     Wound   in  the  middle  of  the  arm  affecting  only  the  inner  part  of  the 

nerve. 
Fig.  166. — Fascicular  topography  of  the  median.     The  inner  part  supplies  the  flexors. 

The  outer  part  supplies  the  pronator  radii  teres,  the  carpi  radialis,  the  palmaris  longus, 

and  the  thenar  eminence. 

accompanied  by  no  sensory  disturbance  whatsoever  ;  in  the  third,  there 
was  somewhat  pronounced  anaesthesia  of  the  distribution  of  the  median. 

In  other  cases,  where  the  lesion  affects  the  nerve  at  its  external  border, 
it  is  rather  the  muscles  of  the  thumb,  the  pronator  radii  teres  and  the 
flexor  carpi  radialis  that  are  paralysed,  the  existence  of  sensory  disturbances 
is  not  invariable. 

It  would  thus  appear  that  the  fibres  destined  for  the  pronator  radii 
teres,  the  flexor  carpi  radialis,  the  flexor  pollicis  and  the  muscles  of  the 
thenar  eminence  occupy  the  outer  part  of  the  median  nerve. 

The  fibres  that  supply  the  flexors,  on  the  other  hand,  are  the  most 
internal. 


MEDIAN    NERVE 


185 


The  sensory  fibres  probably  hold  an  intermediate  position,  since  either 
of  these  motor  syndromes  may  involve  injury  to  them. 

According  to  the  researches  of  Pierre  Marie,  A.  Gosset  and  H.  Meige, 
on  applying  local  electrical  stimulation  to  the  nerve  trunks,  there  are  in  the 
median  nerve,  in  the  arm,  four  distinct  groups  of  motor  fibres  : 

Pronator  muscles  in  the  antero-external  region  of  the  nerve. 

Thenar  muscles  in  the  posterior  region. 

Flexor  muscles  of  the  carpus  in  the  postero-internal  region. 

Flexors  of  the  fingers  in  the  antero-internal  region. 


IV.— NEURITIS  OF  THE  MEDIAN 

An  essential  distinction  must  be  drawn  between  neuritis  of  the  median, 
accompanied  by  considerable  trophic  disturbances,  and  neuralgia  of  the 
median,  both  frequent  and  distinctive,  to  which  the  name  of  causalgia  has 
been  given. 

Nerve  irritation  of  the  median  is 
characterised,  as  is  that  of  all  other 
nerve  trunks  : 

1.  By  spontaneous  and  often 
very  acute  pain  ; 

2.  By  pain  on  pressure  of  the 
nerve  trunks  and  muscular  bellies  ; 

3.  By  painful  hypo-aesthesia  or 
even  by  cutaneous  hyper-aesthesia  ; 

4.  By  important  trophic  disturb- 
ances culminating  in  gr'iffe  of  the 
median. 

We  again  find  in  these  cases 
cutaneous  trophic  disturbances,  scaly 
desquamation  of  the  skin,  and  fibrous 
infiltration  of  the  dermis  ;  but  we 
must  especially  note  two  orders  of 
symptoms  :  disturbances  of  the  nails 
and  the  formation  of  griffe. 

The  nails  of  thumb,  index  and 
middle  finger  are  always  consider- 
ably affected  in  neuritis  of  the  median. 

In  the  pronounced  form,  the  nails  are  striated,  both  longitudinally  and 
transversely,  bent  into  actual  claws  ;  they  grow  extremely  fast,  and  their 
rapid  development  raises  between  the  nail  and  the  digital  pulp  a  small 
cutaneous  swelling  which,  provoked  and  increased  by  the  growth  of  the 
nail,  is  frequently  the  seat  of  somewhat  acute  pain. 

Trophic  disturbances  of  the  nails  in  neuritis  of  the  median  are 
absolutely   constant   and    very  well  defined.      Sometimes    even,   in    slight 


167. — Sub-ungual  swelling  in 
neuritis  of  the  median, 


1 86  NERVE   WOUNDS 

nerve  irritation,  the  nails  alone  are  affected,  and   it  is  their  special   incur- 
vation that  enables  us  to  recognise  the  existence  of  this  irritation. 

Griffe  of  the  median,  in  neuritis  of  this  nerve,  is  far  from  being  as 


Fig.  i 68. — Griffe  of  the  median  caused  by  neuritis.  Deformity  of  the  nails.  Glossy 
skin.  Atrophy  and  fibrous  infiltration  of  the  last  two  phalanges,  especially  of  the 
index. 


constant  and    intense  as   ulnar   griffe.      Still,  it  is  occasionally  found,  or 
suggested  at  all  events. 

It   consists  of  fibrous  contraction  of  the  flexor  tendons  and  synovial 


Fig.  169. — Incurvation  of  the  nails  in  slight  neuritis  of  the  median. 
Immobilisation  of  the  finger  in  extension. 

sheaths,  immobilising  thumb,  index  and  middle  finger  in  moderate  though 
irreducible  flexion.  This  flexion  is  most  pronounced  in  the  last  phalanges  ; 
contraction   of  the    palmar  aponeurosis  is  but   faintly  perceptible  and   its 


MEDIAN    NERVE  187 

relative  integrity  contrasts  with  the  intensity  of  its  disturbances  in  neuritis 
of  the  ulnar. 

Griff?  of  the  median  in  flexion  is  not  altogether  constant  ;  for  in  cases 
of  slight  neuritis  we  often  find  immobilisation  of  the  fingers  in  extension 
along  with  adhesion  of  the  skin  to  the  dorsal  surface  of  the  fingers  and 
fibrous  transformation  of  the  digital  articulations.  Neuritis  of  the  median 
in  these  cases  somewhat  resembles  neuritis  of  the  musculo-spiral  :  but 
whereas  articular  sclerosis  is  more  marked  in  the  case  of  the  first  digital 
articulation,  on  the  other  hand,  when  the  musculo-spiral  is  involved  in 
neuritis  of  the  median,  it  is  the  second  and  third  digital  articulations  that 
arc  specially  affected. 

As  in  all  other  cases  of  nerve   irritation,  the  fibrous  sequelae  left  by 


Fin.  170. — Neuritic  griffe  of  the  median. 

irritation  of  the  median  persist  long  after  the  paralysis  has  been  cured  and 
may  even  terminate  in  irreducible  deformity. 

Neuritis  of  the  median  is  found  both  in  lesions  of  the  nerve,  in  the 
arm,  and  in  irritations  below  the  elbow,  even  at  the  wrist. 

It  may  exist  apart  altogether  from  paralysis,  but,  as  a  rule,  in  such 
cases,  it  somewhat  resembles,  in  the  slight  degree  of  trophic  disturbances 
and  the  intensity  of  painful  phenomena,  neuralgia  of  the  median  in  its 
causalijic  form.     This  we  shall  now  study. 


V.— CAUSALGIA    OF   THE   MEDIAN   NERVE 

Nerve  irritations  of  the  median  assume  with  the  utmost  frequency  and 
intensity  the  type  of  the  causalgia  of  Weir  Mitchell  ;  to  such  an  extent 
is  this  so,  that  causalgia  has  been  regarded  as  peculiar  to  this  nerve. 

Whilst  this  fact  may  not  be  altogether  correct,  whilst  other  nerves, 
particularly  the  sciatic  and  chiefly  the  internal  popliteal,  are  capable  of 
presenting  the  same  disturbances,  none  the  less  is  it  true  that  causalgia  of 
the  median  is  by  far  the  most  frequent  and  characteristic. 


NERVE   WOUNDS 


It  almost  invariably  accompanies  slight  lesion  of  the  nerve,  without 
paralysis  or  anaesthesia,  but  appearing  all  of  a  sudden  and  accompanied  by 
almost  purely  painful  symptoms  and  a  minimum  of  trophic  disturbances. 
***** 
Immediately  after  the  wound  pain  manifests  itself,  but  it  gradually 
increases  during  the  following  days,  usually  reaching  its  culminating  point 
after  ten  or  twenty  days. 

Patients  complain  of  terrible,  intolerable,  persistent,  paroxysmal  pains 
both  day  and  night  ;  these  pains  are  essentially  localised  in  the  hand,  but 
they  spread  over  the  upper  part  of  the  arm,  even  though  the  wound  is  in 
the  fore-arm  or  the  wrist. 

The  pain  is  a  special  and  a  violent  one,  characterised  by  a  sensation  of 
persistent  burning,  whence  the  name  of  causalgia  (icavaig,  burning). 

Cold,  heat,  the  slightest  con- 
tact, cause  the  most  atrocious 
pain.  What  patients  most  dread 
is  contact  with  the  air  and  dryness 
of  the  hand  ;  tepid  water  often 
relieves  them,  and  we  see  them 
wrapping  round  their  hands 
moist  cloths  which  they  con- 
stantly renew.  It  is  also  to  be 
noted  that  profuse  perspiration 
of  the  hand  frequently  takes 
place. 

It  is  not  only  cutaneous  ex- 
citations of  the  hand  that  cause 
painful  paroxysms,  movement  of 
any     kind     is      painful  ;      simple 
swinging     of    the     hand     when 
walking    causes    intolerable    re- 
crudescences   in    these    patients. 
Strong  emotion,  an   approaching 
carriage,  an  unexpected  sound,  the  banging  of  a  door,  a  brilliant  light,  the 
dizzy  sense  of  void  in  a  staircase  ;   any  of  these  may  bring  on  a  terrible 
and  painful  crisis. 

Thus  we  find  in  these  patients  special  symptoms  :  emaciated  by  reason 
of  insomnia  and  loss  of  appetite,  they  are  gloomy  and  peevish,  they  will 
neither  talk  nor  go  outside,  they  seek  solitude,  silence  and  obscurity  ;  they 
walk  slowly,  with  short  steps,  to  avoid  all  shock  ;  if  any  one  approaches 
them,  they  slink  away,  carefully  protecting  the  hand  from  all  contact  by 
concealing  it  behind  the  back,  or  placing  the  other  arm  round  it  as  a 
shield.  The  hand  is  carefully  enveloped  either  with  a  glove  or  with  wet 
cloths,  which  some  of  them  keep  renewing,  even  during  conversation. 

If  these  patients  are  examined,  we  are  surprised   to  find  that  there  is 


Fig.  171. — Position  of  the  hand  at  rest. 
This  is  not  a  paralytic  posture  ;  but  im- 
mobilisation caused  by  pain.     (Dejerine.) 


MEDIAN    NERVE 


189 


no  paralysis  ;  the  hand  is  simply  immobilised  as  a  result  of  pain.  Nor  is 
there  complete  anaesthesia,  though  often  very  intense  and  painful  hyper- 
esthesia ;  more  than  this,  whereas  the  slightest  touch  of  the  skin  causes 
intolerable  suffering,  firm  pressure  on  the  integuments  is  not  very  painful, 
pressure  on  the  muscles  of  the  fore-arm  is  not  at  all  painful,  that  on  the 
nerve  but  slightly,  except  near  the  hand.  It  is  excitation  of  the  surface 
that  is  painful,  not  deep  excitation  as  in  cases  of  neuritis. 

Trophic  and  vaso-motor  disturbances  are  insignificant  and  of  a  rather 
special  nature. 

Usually  the  skin  is  not  thickened  as  in  cases  of  neuritis  ;  on  the  con- 
trary it  is  thin,  smooth  and  glossy,  with  an  onion-rind  appearance.  It  is 
often  red  and  almost  always  moist. 


Fig.  172. — Topography  of  the  disturbances  of  objective  sensibility.  These  disturbances 
extend  beyond  the  cutaneous  region  of  the  median,  a,  Hyperesthesia  to  slight  con- 
tact (wisp  of  cotton  wool).  />,  Hyperesthesia  to  pin-prick,  c,  Hypo-;tsthesia  to  heat. 
Oblique  hatching  .-  the  heat  is  less  distinctly  felt.  Horizontal  hatching  ;  the  heat  is  not 
recognised  as  such.     (J.  and  A.  Dejerine  and  Mouzon,  Presse  Med.,  8  July,  1915.) 


There  is  neither  sclerosis  of  the  dermis,  fibrous  contraction  nor 
articular  immobilisation  ;  the  nails  are  curved  as  in  neuritis,  but  they  arc 
thin  and  smooth,  not  thickened,  split  or  striated.  Moreover,  the)-  grow 
rapidly  and  produce  behind  the  pulp  a  slight  cutaneous  swelling  which  is 
extremely  painful. 

After  a  few  months  there  can  be  seen  taking  place  considerable  atrophy 
of  the  extremities  of  index  and  middle  finger,  thin,  tapering  and  conical 
extremities  which  terminate  in  quite  small  and  almost  triangular  nails. 

Whilst  the  trophic  disturbances  usual  in  cases  of  neuritis  are  absent  in 
causalgia,  special  lesions  are  found  from  time  to  time  ;  we  have  seen  small 
subungual  ecchymoses  or  more  frequently  small  cutaneous  phlyctens,  com- 
parable to  sudamina  which,  on  rupture,  left  a  very  painful  punctiform 
cicatrix.  It  would  seem  that  the  thinness  and  fragility  of  the  integuments, 
the  constantly  damp  condition  and  perhaps  more  especially  the  maceration 


190 


NERVE   WOUNDS 


of  the  continually   moistened   epidermis,   favour  the  appearance  of  these 
trophic  disturbances. 

There  are  cases  of  causalgia  in  which  neurotic  lesions  are  more  mani- 
fest ;  accompanied  by  dryness  of  the  skin,  scaly  desquamation,  fibrous 
infiltration  of  the  dermis  and  a  tendency  to  ankylosis  of  the  last  phalanges. 


Figs.  173  and  174. — Causalgia  of  the  median  nerve.  Tapering  of  the  fingers,  atrophy, 
thinness  of  the  skin,  profuse  sweat.  Sudamina  followed  by  ulceration.  Rapid  growth 
of  nails  and  sub-iingual  swellings. 


Causalgia  of  the  median  is  very  refractory  to  treatment  ;  it  continues 
for  eight,  ten,  or  even  fifteen  months,  before  diminishing  and  finally 
disappearing.  Massage  has  no  result  whatsoever,  galvanic  electrical 
stimulation  with  the  positive  pole,  and  iodine  or  salicylic  ionisation  cause 
only  a  few  hours'  relief;  in  these  conditions  it  may  readily  be  understood 


MEDIAN    NERVE 


191 


that  there  has  been  strong  temptation  to  practise  resection  and  suture  or 
alcoholisation  (Sicard)  of  the  affected  nerve. 

At  the  same  time,  one  hesitates  before  subjecting  these  patients,  who 
are  not  paralysed,  to  the  risks  of  nerve  suture. 

Radiotherapy  to  the  nerve  itself  or  to  the  roots  frequently  alleviates 
causalgia,  but  it  only  dispels  the  painful  paroxysms  and  does  not  calm  the 
continuous  dull  pain. 


Fig.  175. — Causalgia  of  the  median  nerve,  with  incurvation  of  the  nails,  conical  atrophy 
of  the  last  phalanges,  fibrous  infiltration  of  dermis  and  digital  articulations.  (Com- 
pare index  and  middle  finger  with  the  comparatively  unaffected  ring-finger. 

Moreover,  its  effect  is  not  constant. 

At  present,  there  is  a  tendency  to  regard  causalgia  as  a  sympathetic 
syndrome.  Undoubtedly  vaso-dilatation  or  vasoconstriction  of  the  skin, 
profuse  sweats,  and  the  recrudescence  of  pain  through  emotion,  call  forth 
the  idea  of  sympathetic  disturbances.     (Leriche,  Meige  and  Mine.  Benisty.) 

In  causalgia  caused  by  wounds  at  wrist  or  in  the  fore-arm,  we  have 
found  disturbances  throughout  the  entire  region  of  the  cervical  sympathetic, 
with  narrowing  and  vaso-constriction  of  the  entire  brachial  artery  whose 
calibre  was  not  more  than  two  or  three  millimetres  and  whose  pulsations 
were  almost  non-existent  ;  there  was  also  slight  numbness  of  the  surface 
on  the  same  side,  a  diminution  of  sweat,  vaso-motor  disturbances  in  the  ear 
on  the  affected  side,  manifestly  proving  the  existence  of  reflex  excitation 
of  the  cervical  sympathetic. 


192 


NERVE    WOUNDS 


All  these  facts  may  justify  the  intervention  proposed  by  Leriche  : 
denudation  of  the  brachial  artery  and  resection  of  the  sympathetic  plexus 
surrounding  it.  We  have  performed  this  operation  several  times  with 
favourable  results  in  cases  refractory  to  all  other  treatment. 


DIAGNOSIS  OF  PARALYSIS  OF  THE  MEDIAN   NERVE 
We  need   not  insist  on  the  possibility  of  overlooking  paralysis  of  the 
median,   either  above  the  epitrochlear  muscles,  when  flexion  of  the  first 


Figs.  176  and  177. — Pseudo-paralysis  of  the  median,  Lesion  of  the  nerve  in  the  tore- 
arm.  Cutaneous  anesthesia  and  atrophy  of  the  thenar  eminence.  Although  the 
flexors  are  intact,  the  patient  cannot  close  his  hand  completely.  Faradisation  ot  the 
flexors  readily  produces  movement.     Cure  effected  by  a  single  treatment. 

phalanges  by  the  interossei  might  incline  one  to  believe  in  the  possibility 
of  some  slight  action  of  the  flexors,  or  below  the  epitrochlear  muscles, 
where  all  the  disturbances  are  reduced  to  cutaneous  anaesthesia  and  to  the 
loss  of  opposition  of  the  thumb. 


MEDIAN    NERVE  193 

Wounds  of  the  fore-arm,  in  which  the  median  nerve  is  affected,  very 
often  cause,  from  injury  to  the  muscles,  a  weakening  or  even  complete 
incapacity  of  the  flexors  of  the  fingers,  that  might  erroneously  be  attributed 
to  nerve  lesion. 

To  avoid  this  error,  we  must  remember  that  the  flexors  receive  their 
nerve  twigs  very  high  up,  immediately  below  the  bend  of  the  elbow  ; 
moreover,  the  muscles  weakened  by  the  wound  retain  more  or  less  their 
normal  electrical  reactions  and  above  all  their  faradic  excitability. 

It  is  also  known  that  there  is  frequently  associated  with  these  wounds 
a  certain  degree  of  functional  paralysis  due  to  prolonged  inaction. 

Here  we  would  point  out  a  somewhat  frequent  cause  of  error,  to  which 
allusion  has  already  been  made.  We  refer  to  functional  paralysis  of  the 
flexors  of  the  thumb,  the  index  and  the  middle  finger,  following  lesion  of 
the  median  in  the  fore-arm  and  caused  by  anaesthesia  of  the  hand. 

We  have  met  with  several  of  these  very  curious  cases  in  which  the 
patient  thinks  that  his  fingers  are  paralysed  because  he  neither  feels  them 
nor  even  attempts  to  use  them. 

We  need  only  contract  the  flexors  by  means  of  the  faradic  current  to 
recognise  the  functional  nature  of  this  paralysis,  prove  to  the  patient  the 
possibility  of  movement,  and  effect  a  speedy  cure. 


'3 


CHAPTER    IX 

ASSOCIATED   PARALYSIS   OF  THE   MEDIAN 
AND  ULNAR   NERVES 

It  is  necessary  to  make  a  special  study  of  the  associated  paralyses  of  the 
median    and    the    ulnar.       These    paralyses    are    very   frequent,  and   are 


Fig.  178. — Paralysis  of  the  median  and  the  ulnar — "flat  hand." 

caused   by  lesions  in  the  upper  arm,  where  both  nerves  are  close  to  each 
other. 


Fig.  179. — Paralysis  of  the  median  and  the  ulnar.    Hyper-extension  of  the  first  phalanges 

by  contraction  of  the  extensors.      This   movement   induces   semi-flexion  of   the  second 
and  third  phalanges  (paralysis  of  the  interossei). 

In  these  cases  we  note  the  association  of  the  two  paralytic  syndromes, 
also  complete  loss  of  the  movements  of  flexors  and  interossei. 


PARALYSIS    OF    MEDIAN    AND    ULNAR    NERVES     195 


Atrophy  of  the  epitrochlcar  muscles  is  complete  ;  the  massive  atrophy 

of  the  thenar  and  hypothenar  muscles  produces  the  "  flat  hand  "  appearance. 
Owing  to  atony  of  the 

flexors  and   interossci,  the 

efforts  to  extend  the  fingers 

readily  induce  an  attitude 

of  hyper-extension  of  the 

first  phalanges,  along  with 

semi-flexion  of  the  second 

and  third. 

Particularly  important 

are    the    curious   substitu- 
tionary  movements  found 

in    most    cases    and    first 

mentioned  by  H.  Claude. 
Flexion  of  the  hand  on 

the    wrist   is    theoretically 

suppressed  ;  all   the  same, 

it    is    for    the    most     part 

possible,  by  substitution  of 

the    extensor   ossis    meta- 

carpi  pollicis  and  the  short  extensor  of  the  thumb. 

Finger-flexion  is  logically  impossible.      Patients,  however,  are  capable 

of  performing  certain  flexion  movements  ;  to  such  an  extent  is  this  the  case, 

that  it  is  difficult  to  believe  that  both  nerves  are  paralysed. 

They  succeed  in  flexing  the  fingers  by 
forcibly  raising  the  hand  with  the  radial 
extensors  ;  the  effect  of  this  hollowing  of  the 
hand  is  to  stretch  the  flexor  tendons  on  the 
pulley,  as  it  were,  of  the  radio-carpal  articu- 
lation, and  consequently  to  exercise  traction 
on  the  fingers,  in  a  purely  mechanical  way. 

Again,  in  raising  the  hand,  the  patients 
allow  their  fingers  to  droop  under  the  action 
of  gravity,  and  this  still  further  emphasises 
the  flexion  attitude.     This  may  be  seen  by 


Fig.  180. — Flexion  of  the  hand  by  the  extensor  ossis 
metacarpi  pollicis  and  by  the  short  extensor  of  the 
thumb.  (Claude,  Dumas,  and  Porack,  Presse  Med., 
10  June,  191 5.) 


and  mechanical  traction  of  the 
flexor  tendon*. 


1"k..  1  S 1 . — Pseudo-flexion  or  the 
fingers.  In  paralysis  of  the 
median  and  the  ulnar,  by  torci- 
ble  straightening  of  the  carpus    turning  upwards  the   palm  of  the  hand;   the 

action    of   gravity   ceases,    and    the    fingers, 
being  flexed  only  by   the    hollowing    of    the 
hand,  fall  back  into  a  state  of  moderate  flexion. 

It  is  unnecessary  to  add  that  this  artificial  flexion  of  the  fingers  is 
extremely  feeble  and  cannot  be  made  use  of  by  the  patient. 

When  regeneration  begins  in  the  median  and  ulnar  nerves,  there  is 
observed  the  progressive  appearance  of  a  special  four-fingered  g)'tjff''y  supple 
and   reducible,  characterised   by  flexion  of  the  last  two  phalanges  on  the 


196 


NERVE   WOUNDS 


first  :   it  is  produced  by  tone  of  the  flexors  of  the  fingers,  deprived  of  the 
antagonism  of  the  interossei,  extensors  of  the  last  two  phalanges. 


Figs.  182  and  183. — Paralysis  of  the  median  and  the  ulnar  in  course  of  regeneration. 
The  "  flat  "  hand  has  become  transformed  into  a  four-fingered  griff e  once  the  flexors 
have  regained  their  tone.  (Soft  and  reducible  griffe.)  Note  the  projection  ot  the 
flexor  carpi  radialis. 


Finally,  simultaneous  irritation  of  the 
median  and  the  ulnar  causes  a  complete 
neuritic  fibrous  four-fingered  griffe  ;  flat- 
tening of  the  thenar  and  hypothenar  emi- 
nences, atrophy  of  the  interossei,  and 
flexion  of  the  last  two  phalanges,  all  give 
the  hand  the  typical  appearance  of  the 
"  ape-like  hand." 


Figs.  184  and  185. — Neuritic  griffe  or  the  median  and  the  ulnar — "simian  hand."    Fibrous 
four-fingered  griffe.     Tendon  contraction.      Contraction  of  the  palmar  aponeurosis. 


CHAPTER   X 

MUSCULOCUTANEOUS   NERVE 

The  musculocutaneous  nerve  originates  along  with  the  external  root  of 
the  median  from  the  outer  cord  of  the  brachial  plexus.  Its  fibres  arise 
almost  solelv  from  the  fifth  and  sixth  cervical  roots. 


Branch  to  brach.  ant. 


Anastomosis  of  median  an 
musculo-cutaneous 


Musculo-cutaneous  nerve 

Musculo-spiral  nerve 

Musculo-spiral  (external  branch) 


Musculo  cutaneous  nerve 
Branch  to  the  coraco-brachialis 

Internal  cutaneous  nerve 
Branch  to  the  biceps 

Median  nerve 
Ulnar  nerve 


Internal  cutaneous  nerve  (internal 
branch) 


Anterior  aspect. 

Fig.  i  86. — Deep  nerves  of  arm  (after  Sappey).     The  biceps  has  been  resected 
to  lay  hare  the  musculocutaneous  nerve. 

At  its  origin  in  the  armpit,  the  musculo-cutaneous  nerve  is  situated 
above  and  outside  the  median  and  the  axillary  artery.  It  remains 
adherent  to  the  median,  as  far  as  the  union  of  the  upper  third  and  the 
middle  third  of  the  arm. 


198 


NERVE   WOUNDS 


At  this  level  it  suddenly  changes  direction,  passes  obliquely  outward, 
crosses  the  coraco-brachialis,  and  descends  obliquely  in  front  of  the 
brachialis  anticus,  covered  by  the  biceps,  supplying  motor  branches  to 
these  three  muscles. 

It  is  under  the  biceps  that  the  anastomotic  branch  breaks  away,  uniting 
the  musculo-cutaneous  to  the  median  nerve  ;  rising  again  obliquely  it 
enters  this  nerve,  reaching  it  at  the  middle  third  of  the  arm. 

Probably  it  often  brings  to  the  median  aberrant  motor  fibres  issuing 
from  the  fifth  and  sixth  cervical  roots. 


Posterior  surface.  Anterior  surface. 

Fig.  187.  Fig.  188.  Fig.  189. 

Figs.  187  and  188. — Sensory  region  of  musculo-cutaneous  nerve. 

Fig.  189. — Cutaneous  anesthesia  in  complete  section  of  musculo-cutaneous  nerve. 

Afterwards  the  musculo-cutaneous  nerve  appears  on  the  external 
surface  of  the  biceps,  plunges  underneath  the  edge  of  the  supinator 
longus,  and  becomes  sub-cutaneous  near  the  bend  of  the  elbow  ;  it  then 
divides  into  its  two  terminal  branches,  anterior  and  posterior,  which 
descend  in  parallel  lines  on  to  the  antero-external  surface  of  the  fore-arm, 
supplying  the  skin. 

Branches 

I.  Along  the  first  part  of  its  course,  the  musculo-cutaneous  supplies 
only  motor-branches  : 

The  nerves  to  the  coraco-brachialis. 


musculo-cutanp:ous  nerve 


[99 


The  nerves  to  the  biceps. 

The  nerves  to  the  brachialis  amicus. 

2.  Beyond  the  biceps,  the  musculo-cutaneous  is  no  more  than  a  sensory 
nerve  where  two  parallel  branches  of  the  bifurcation  supply  the  antero- 
ihternal  part  of  the  fore-arm  right  to  the  vicinity  of  the  wrist. 

3.  Lastly,  the  musculo-cutaneous,  apart  from  its  terminal  anastomoses, 
sends  out  an   important  anastomotic   branch  to   the   median,  meeting;  the 


Fig.  190.  Fig.  191. 

Fig.    190. — Substitution    of    the  paralysed    musculo-eutaneous    by  the    musculo-Bpiral. 

Energetic  flexion  of  the  fore-arm  on  the  arm  by  the  supinator. 
Fig.    191. — Muscles  supplied    by    the    musculo-cutaneous.       Coraco-brachialis    biceps  ; 

brachialis  amicus.     The  deltoid  is  cut  in  order  to  expose  the  deep  muscles. 

latter  about  the  middle  of  the  arm.  It  seems  to  be  proved  that,  speaking 
generally,  this  branch  brings  to  the  median  supplementary  fibres  of  the 
fifth  and  sixth  cervical  roots  ;  it  mav  fail  in  this;  the  thinner  the  external 
head  of  the  median,  the  more  developed  this  branch  is. 


200  NERVE   WOUNDS 

PHYSIOLOGY— PARALYSIS  OF  THE   MUSCULO-CUTANEOUS 

Motor  Syndrome 

The  musculo-cutaneous  is  the  nerve  whose  sole  function  is  to  supply 
the  flexors  of  the  fore-arm  on  the  arm. 

Its  interruption  determines  paralysis  and  atrophy  of  the  coraco- 
brachialis,  the  biceps  and  the  brachialis  anticus  ;  these  last  two  are  flexors 
of  the  fore-arm  on  the  arm. 

It  must  not  be  imagined  that  paralysis  of  the  musculo-cutaneous  does 
away  with  the  flexion  of  the  elbow.  This  is  still  possible,  even  forcibly, 
by  the  supinator  longus  (musculo-spiral),  the  flexor  role  of  which  is  thus 
proved. 

Paralysis  of  this  nerve  may  thus  easily  be  disregarded  if  we  confine 
ourselves  to  making  a  simple  flexion  of  the  fore-arm  without  endeavouring 
to  obtain  real  contraction  of  the  biceps  and  without  exploring  its  electrical 
reactions. 

Sensory  Syndrome 

The  musculo-cutaneous  supplies  the  integuments  of  the  antero- 
external  part  of  the  fore-arm  and  passes  slightly  on  to  its  postero-external 
surface. 

Nevertheless,  we  must  not  expect  to  find  so  extensive  a  state  of 
anaesthesia  in  lesions  of  this  nerve.  The  musculo-spiral  behind,  and  the 
internal  cutaneous  on  the  inner  side,  overlap  it  considerably  and  largely 
reduce  the  region  of  complete  anaesthesia,  which  is  restricted  to  a  tract 
extending  over  the  antero-external  part  of  the  fore-arm. 


CHAPTER    XI 

THE  CIRCUMFLEX  NERVE 

The  circumflex  nerve  is  generally  regarded  as  a  collateral   branch  of  the 
brachial  plexus. 

By  reason  of  its  size  and  importance,  however,  we  may,  with  Sappey, 
regard  it  as  a  terminal  branch  of  this  plexus,  becoming  detached  along 
with  the  musculo-spiral  from  the  posterior  secondary  trunk.  Most  of  its 
fibres  originate  in  the  fifth  cervical  root. 


Supra-scapular  nerve 

Branch  to  the  supra  - 

spinatus 

Branch  to  the  sub- 
spinatu; 


Muscular  branch 

Branch  to  the  teres 
minor 

Muscular  nerve 

Cutaneous  nerve  to 
shoulder 


Fig.  192. — Circumflex  and  supra-scapular  nerves.     (After  Sappey.) 

It  springs  from  the  brachial  plexus,  about  the  middle  of  the  axilla  ;  at 
this  level  it  is  situated  behind  the  axillary  artery,  and  outside  the  musculo- 
spiral  nerve. 

It  immediately  proceeds  downwards  and  outwards,  and  passes  towards 
the  posterior  part  of  the  shoulder  accompanied  by  the  posterior  circumflex 
artery  ;  it  passes  into  the  interspace  circumscribed  by  the  neck  of  the 
humerus  outwards  and  forwards,  the  long  head  of  the  triceps  within  and 
behind,  the  lower  edge  of  the  subscapulars  and  of  the  teres  minor  above, 
the  upper  border  of  the  teres  major  below  (quadrilateral  square  of 
Velpeau). 

It  thus  passes  round  the  posterior  surface  of  the  surgical  neck  of  the 
humerus  and  reaches  the  deltoid  on  its  deep  surface. 


202 


NERVE   WOUNDS 


Branches 

Apart  from  the  articular  branches  and  from  certain  fibres  supplied  to 
the  subscapulars,  the  only  important  offshoots  supplied  by  the  circumflex 
are  the  deltoid  branches  and  the  cutaneous  branch  to  the  shoulder. 

I.  The  deltoid  branches  issue  from  the  circumflex  nerve  after  it  has 


Supra-acromial  branch 


Circumflex  nerve  (cutan- 
eous branch) 


Muscitlo-spiral  nerve  (ex 
cut.  br.) 


Lesser  internal  cutaneous  (ext. 

branch) 
Circumflex  nerve  (cut.  br.) 
Second  intercostal  nerve 


Third  intercostal  nerve 


Musculo-spiral  nerve  (int.  cut. 
br.) 


-Internal  cutaneous  (post,  branch) 


Internal  cutaneous  neive  (ant. 
branch) 


Musculocutaneous  nerve 

LeVeU-LE    S/4LLE* 

Posterior  aspect. 
Fig.  193. — Superficial  nerves  of  shoulder,  arm  and  elbow.     (After  Sappey.) 

reached  the  neck  of  the  humerus.  A  distinction  is  made  between  the 
ascending  and  the  descending  branches,  which  successively  become 
detached  to  supply  the  different  portions  of  the  deltoid. 

This  distribution  is  arranged  in  vertical  segments,  from  behind  for- 
wards. Thus  we  see  that  certain  lesions  of  the  nerve,  on  the  external 
surface  of  the  shoulder,  for  instance,  may  produce  dissociated  paralyses  of 
the  circumflex  ;  the  anterior  and  exterior  fasciculi,  clavicular  and  acromial, 
are  paralysed,  whilst  the  posterior  scapular  fasciculi  are  untouched. 


THE   CIRCUMFLEX    NERVE 


203 


2.  The  cutaneous  nerve  of  the  shoulder  is  a  collateral  sensory  branch, 
which  breaks  away  from  the  circumflex  after  its  passage  into  the  quadri- 
lateral space  ;  it  proceeds  downwards  and  outwards,  and  emerges  between 
the  deltoid  and  the  long  head  of  the  triceps.  Then  it  divides  into 
ascending  and  horizontal  branches  which  supply  the  cutaneous  covering 
for  the  shoulder,  and  in  descending  branches  which  are  distributed  over 
the  integuments  of  the  external  surface. 


PARALYSIS   OF   THE   CIRCUMFLEX 

Paralysis  of  the  circumflex  is  not  met  with  in  direct  traumatisms  of  the 
nerve  only,  it  also  appears  in  fractures  of  the  surgical  neck  of  the  humerus 
by  embedding  or  compression  of  the 
nerve  :   it    may  follow  dislocation  of  the 


FlG.  194. — Paralysis  of  the  circumflex.      Atrophy 
of  the  deltoid. 


FlG.  J95.  —  Motor  area  <>t  t lu 
circumflex. 


shoulder,  owing  to  traction  on  or  contusion  of  the  nerve;  all  the  same, 
it  would  appear  that  in  most  of  these  cases  we  are  dealing  with  the  lesion 
of  the  upper  roots  of  the  brachial  plexus,  stretched  or  torn  away  by  the 
dislocation  (Duval  and  Guillain)  ;  in  reality,  they  are  cases  of  root 
paralysis  of  the  brachial  plexus,  affecting  the  fifth  cervical  root. 


204 


NERVE   WOUNDS 


Lesions  of  the  circumflex  are  shown  solely  by  paralysis  of  the  deltoid 
and  by  sensory  disturbances  of  the  shoulder. 

Paralysis  of  the  deltoid  produces  loss  of  power  to  raise  the  arm  out- 
wards (by  means  of  the  acromial  fasciculi),  forwards  (clavicular  fasciculi), 
and  backwards  (scapular  fasciculi). 

The  disturbances  thus  produced  are  all  the  more  serious  because  sub- 
stitutionary movements  scarcely  exist  at  all  in  the  case  of  the  deltoid. 
The  supra-spinatus  alone  is  capable  of  slightly  raising  the  arm  outwards 
and  forwards,  with  rotation  inwards  ;  this  movement  is  extremely  feeble, 
and  is  incapable  of  introducing  any  effective  substitution  for  paralysis  of 
the  deltoid. 

The  arm  remains  hanging  almost  loose  alongside  the  body  ;  in  vain 
does  the  patient  attempt  to  raise  it  ;  he  contracts  his  shoulder  muscles  and 
the  supra-spinatus  succeeds  in  making  only  a  faint 
movement  of  abduction  ;  he  contracts  the  serratus 
magnus,  but  the  swinging  movement  imparted  to 
the  shoulder-blade  is  nullified  by  the  utter  flaccidity 


Figs.  196  and  197. — Anatomical  sensory  topography 
of  the  circumflex  nerve  (cutaneous  nerve  of  the 
shoulder). 


Fig.  198. — Actual  anesthe- 
sia in  section  of  the  cir- 
cumflex. 


of  the  deltoid  ;  finally,  he  partially  detaches  his  arm  artificially,  by  raising  his 
shoulder  and  bending  his  thorax  in  such  a  way  that  the  arm  is,  as  it  were, 
raised  by  the  ribs  on  which  it  is  resting. 

At  the  same  time  atrophy  of  the  deltoid  flattens  the  shoulder  and 
relaxes  the  joint  capsule,  which  often  exhibits  an  abnormal  degree  of 
laxity. 


SENSORY   DISTURBANCES 

Sensory  disturbances  are  somewhat  reduced  in  paralysis  of  the  cir- 
cumflex. Seldom  do  we  find  complete  anaesthesia  ;  as  a  rule,  we  simply 
have  more  or  less  pronounced  hypo-aesthesia  of  the  external  surface 
of  the  shoulder. 


CHAPTER  XII 

INTERNAL   CUTANEOUS   NERVE  AND  LESSER 
INTERNAL  CUTANEOUS  NERVE 

The  internal  cutaneous  nerve  and  the  lesser  internal  cutaneous  are  very 
seldom  affected  separately  ;  on  the  contrary,  they  often  share  in  the  lesions 
of  the  median  and  the  ulnar,  on  the  inner  surface  of  the  arm. 


Supra-acromtal  branch 

Lesser  int.  cut.  N. 
1  2nd  intercostal 

Int.  cut.  N.  (upper  arm  branch) 
Int.  cut.  N. 


Cut.  br.  of  shoulder 


(  Post,  branch 
I. Ant.  branch 


Ulnar  nerve 


Musculo-spiral  nerve  (ext.  cut.  br.) 


Muse. -cut.  N. 


Mus.-spir.  N.  (ext.  cut.  br.) 


Anterior  aspect. 
Fig.  199.— Cutaneous  nerve  of  shoulder  and  arm.     (After  Sappey.) 

These  are  exclusively  sensory  nerves,  originating  in  the  lower  secondary 
trunk  slightly  internal  to  the  ulnar. 

The  internal  cutaneous  descends  to  the  inner  part  of  the  arm   internal 


2o6 


NERVE   WOUNDS 


to  the  median  nerve,  in  front  of  the  ulnar  nerve  ;  on  reaching  the  middle 
of  the  arm,  it  perforates  the  deep  fascia  and  becomes  superficial.  Then  it 
proceeds  along  the  basilic  vein  and  at  the  bend  of  the  elbow  divides  into 
its  terminal  branches  which  are  distributed  over  the  inner  and  anterior 
part  of  the  fore-arm. 

At  the  base  of  the  axilla,  it  supplies  the  cutaneous  branch  to  the  upper 


Mus.-spir.  N.  (ext.  br.) 
Musculo-cutaneous  N. 


Mus.  cut.  N.  (ant.  br.) 
Mus.  cut.  N.  (post,  br.) 


Mus.  cut.  N.  (ant.  br.) 


Anastom.  of  mus.  cut.  and  radial  $ 


Collar 


pollic.  J 


Int.  cut.  N.  (brachialis  anticus, 
ext.  br.) 


Int.  cut.  N.  (ant.  branch,  inter- 
nal twig) 


Anastom.  of  int.  cut.  and  ulnar 


Palm.  cut.  br.  of  median 


Digital  collateral  trunks 


Anterior  aspect. 
Fig.  200. — Superficial  nerves  of  fore-arm  and  hand.     (After  Sappey.) 

arm,  which  is  distributed  over  the  inner  surface  of  the  arm,  as  far  as  the 
bend  of  the  elbow. 

The  lesser  internal  cutaneous  perforates  the  deep  fascia  at  the  upper 
third  of  the  arm  and  is  distributed  over  the  skin  of  the  inner  surface  of  the 
arm  behind  the  region  of  the  internal  cutaneous  (cutaneous  branch  to  the 
arm)  and  right  to  the  level  of  the  epitrochlea. 

A  lesion  of  the  internal  cutaneous,  usually  associated  with  that  of  the 
median  and  more  especially  of  the  ulnar,  is  shown  by  slight  hypo-aesthesia 
of  the  inner  surface  of  the  fore-arm. 

Only  lesions  which  involve  the  nerve  in  the  neighbourhood  of  the 
axilla    are    accompanied    with    hypo-aesthesia    on    the    inner    surface    of 


INTERNAL    CUTANEOUS    NERVE 


207 


the  arm  ;  and  even  this  hyperesthesia  is  greatly  lessened  owing  to 
the  proximity  of  the  lateral  cutaneous  branches  of  the  second  and  third 
intercostal  nerves. 


Musculo-spiral  N.  (ext.  br.) 


Muse.  cut.  N.  (post,  branch) 


R;ul.  N.  (am.  branch  )Tj  ;' 


Int.  cut.  N.  (post,  branch) 


Int.  cut.  N.  (ant.  branch) 


GHn      >  Ulnar  nerve  (dorsal  branch) 
Rail.  N.  ^collat.  br.)-]     Jl^fh< 

I  if 


Posterior  aspect. 
Fig.  201. — Superficial  nerves  of  fore-arm  ami  hand.     (After  Sappey.) 


208 


NERVE   WOUNDS 


Figs.  202  and  203.  Fig.  204. 

Figs.  202  and  203. — Cutaneous  topography  of  the  internal  cutaneous  and  the  lesser 
internal  cutaneous  (oblique  hatching).  The  perforating  branches  of  the  second  and 
third  intercostal  nerves  supply  a  triangular  area  on  the  postero-internal  surface  of  the 
arm,  in  the  region  of  the  lesser  internal  cutaneous. 

Fig.  204. — Sensory  disturbances  in  lesions  of  the  internal  cutaneous. 


CHAPTER    XIII 

BRACHIAL   PLEXUS 

The  brachial    plexus    consists   of   the    fifth,  sixth,   seventh,    and    eighth 
cervical  roots  and  the  first  dorsal. 

All  these  roots  make  their  way  towards  the  apex  of  the  axilla,  the 


Fig.  205. — Brachial  plexus  and  its  collateral  branches.  (After  Hirschfeld.)  1.  Ansa 
hypoglossi.  2.  Pneumogastric  nerve.  3.  Phrenic  nerve.  4,  5,  6,  7.  Fifth,  sixth, 
seventh  and  tight  cervical  roots.  8.  First  dorsal  root.  9.  Nerve  to  the  subclavius. 
10.  Nerve  to  serratus  magnus.  11.  Nerve  to  pectoralis  major.  12.  Sub-scapular 
nerve.  13.  Nerve  to  pectoralis  minor.  14.  Anastomoses  of  nerves  of  pectoralis  major 
and  pectoralis  minor.  15.  Lower  branch  to  sub-scapularis.  16.  Nerve  to  teres  major. 
17.  Nerve  to  latissimus  dorsi.  18,20,21.  L.I.C.  19.  Its  anastomosis  with  the  lateral 
cutaneous  branch  of"  the  second  intercostal  nerve.  22.  Internal  cutaneous  nerve. 
23.  Ulnar  nerve.  24.  Median  nerve.  25.  Musculocutaneous  nerve.  26.  Musculo- 
spiral  nerve. 

14 


210 


NERVE   WOUNDS 


higher  ones  taking  an  obliquely  descending  course,  the  lower  ones  following 
a  direction  almost  horizontal. 

The  brachial  plexus  thus  spreads  out  into  the  sub-clavicular  region  in 
the  form  of  a  triangle,  with  vertebral  base  and  axillary  apex. 

Near  the  vertebral  column,  the  roots  of  the  plexus,  set  in  tiers  and 
separated  from  one  another,  may  be  affected  separately  by  traumatism, 
whereas  wounds  in  the  axillary  region  almost  invariably  cause  important 
injuries  that  affect  several  trunks. 

CONSTITUTION  OF  THE   BRACHIAL   PLEXUS 

There  are  many  individual  variations  in  the  constitution  of  the  plexus  ; 
at  the  same  time,  we  can  give  a  tolerably  simple  diagrammatic  description 
of  it. 

I.— PRIMARY   TRUNKS 

The  fifth  and  sixth  cervical  roots  unite  to  constitute  the  upper  trunk. 
The  eighth  cervical   and   the  first  dorsal  join  to  constitute  the  lower 
trunk.     The  seventh  cervical  of  itself  forms  the  middle  trunk. 


II.— SECONDARY  TRUNKS 
Each  of  the  primary  trunks  soon  divides  into  two  branches,  the  one 


anterior,  the  other  posterior. 


Fie.  206. — Constitution  of  the  brachial  plexus. 


The  anterior  branches  of  the  upper  trunk  and  of  the  middle  trunk 
unite  to  form  the  upper  cord  which  is  to  produce  the  musculo-cutaneous 
nerve  and  the  external  or  superior  root  of  the  median. 

The  anterior  branch  of  the  lower  trunk  constitutes  of  itself   the  inner 


BRACHIAL    PLEXUS 


21  I 


cord,  which  produces  the  ulnar  and  the  inner  root  of  the  median  as  well 
as  the  internal  cutaneous  and  lesser  internal  cutaneous. 

The  three  posterior  branches  unite  to  form  the  posterior  cord  which 
supplies  the  circumflex  and  afterwards  constitutes  the  musculo-spiral 
nerve. 


Connexions  of  the  Brachial  Plexus 

On  leaving  the  intervertebral  foramina,  the  roots  of  the  brachial 
plexus  penetrate  into  the  space  separating  the  scalenus  anticus  from  the 
scalenus  medius. 

Then  they  cross  obliquely  the  lower  part  of  the  supra-clavicular  fossa 
and  converge  towards  the  middle  of  the  clavicle.     It  is  slightly  outside  the 


Pectoralis  minor 


Musculo-spiral  ™ 
Fig.  207. — Connexions  of  the  brachial  plexus  at  the  level  of  the  axilla. 

scaleni  that  the  primary  trunks  appear.  Thus  the  supra-clavicular  area 
is  essentially  that  of  the  primary  trunks  and  of  their  branches  of  division. 

Below  the  clavicle  are  found  the  cords  which  soon  produce  the  nerves 
of  the  upper  limb. 

The  important  relation  of  the  brachial  plexus  with  the  axillary 
artery  and  vein  are  well  known. 

Situated  at  first  external  to,  and  a  little  behind  the  axillary  artery, 
which  separates  them  from  the  vein  situated  more  internally,  the  nerve 
trunks  are  all  around  the  artery  ;  the  musculo-cutaneous  is  outside  and 
above,  the  median   in   front  and  outside,  the  musculo-spiral  behind  ;  the 


212  NERVE   WOUNDS 

ulnar  runs  between  the  artery  and  the  vein ;  the  inner  head  of  the 
median,  passing  between  the  artery  and  the  vein,  crosses  the  anterior 
surface  of  the  artery. 

Traumatisms  which  affect  the  brachial  plexus  will  accordingly  affect 
the  different  groupings  of  nerve  fibres,  according  to  the  level  of  the 
wound. 

We  must  remember  that  the  brachial  plexus  may  somewhat  diagram- 
matically  be  divided  into  four  regions. 

In  the  region  of  the  scaleni,  and  even  a  little  outside  this  zone,  are 
found  the  roots  of  the  plexus. 

The  supra-clavicular  fossa  corresponds  to  the  region  of  the  primary 
trunks. 

Behind  the  clavicle  and  in  the  upper  part  of  the  axilla,  are  found  the 
secondary  cords.  In  the  lower  axillary  region  appear  the  nerves  of  the 
upper  limb. 

It  is  necessary  to  add  that  the  nerve  fibres  all  converge  upon  the  axilla ; 
at  this  level,  lesions  of  the  plexus  will  often  be  severe  and  very  extensive, 
affecting  several  nerve  trunks  and  simultaneously  affecting  the  axillary 
vessels.  Wounds  of  the  supra-clavicular  fossa,  especially  those  of  the 
region  of  the  scaleni,  on  the  other  hand,  affect  isolated  nerve  trunks  ; 
most  frequently  they  induce  partial  lesions  and  dissociated  root  paralyses  ; 
the  artery  and  the  axillary  vein,  situated  much  lower,  behind  the  clavicle, 
are  more  rarely  affected. 

Branches  of  the  Brachial  Plexus 

Along  its  course  the  brachial  plexus  sends  out  a  certain  number  of 
important  collateral  branches. 

1.  The  nerve  to  the  rhomboids  which  separates  direct  from  the  fifth 
cervical  root. 

2.  The  nerve  to  the  serratus  magnus,  which  originates  in  the  fifth 
and  sixth  cervical  roots,  crosses  the  entire  posterior  surface  of  the  brachial 
plexus  and  descends  along  the  mid-axillary  line,  adhering  to  the  thoracic 
wall. 

3.  The  supra-scapular  nerve,  springing  from  the  higher  primary  trunk 
crosses  the  supra-clavicular  fossa,  reaches  the  supra-scapular  notch  passing 
beneath  the  ligament  which  converts  into  a  foramen  the  supra-scapular 
notch  whilst  the  supra-scapular  vessels  pass  above  it.  It  thus  penetrates 
into  the  supra-spinous  fossa,  passes  round  the  spine  of  the  scapula  and 
terminates  in  the  infra-spinous  fossa. 

It  supplies  the  supra  and  infra  spinati. 

4.  The  upper  branch  to  the  subscapulars,  originating  in  the  upper 
trunk. 

5.  The  nerve  to  the  subclavius  rises  generally  in  the  anterior  branch 


BRACHIAL    PLEXUS 


213 


of  the   upper  trunk  and    supplies  an  anastomotic    branch   to   the  phrenic 
(loop  of  Henle). 


Supra-scapular  net 

Branch  to  supra- 
spinatus 

Branch  to  infra- 
spinatus 


l8Cu]ai  I  ranch 

{ranch  to  teres  minor 
Circumflex  nerve 


Muscular  branch 

Cutaneous  twig  to 
shoulder 


Fig.  208. — Circumflex  and  supra-scapular  nerves.     (After  Sappey.) 


IV  C 


Infrnnr  rervi'-jt 
ganglion 


Fig.  209. — Collateral  branches  of  the  brachial  plexus. 


6.  The  nerve  to    the    pectoralis    major    (external    anterior    thoracic) 
separates  from  the  upper  cord  behind  the  clavicle. 

7.  The  lower  branch  to  the  subscapular^. 

8.  The  nerve  to  the  teres  major. 

9.  The  nerve  to  the  latissimus  dorsi. 


2i4  NERVE   WOUNDS 

These  three  nerves  become  detached  almost  at  the  same  level  from 
the  posterior  cord,  near  the  origin  of  the  circumflex. 

io.  The  nerve  to  the  pectoralis  minor  (internal  anterior  thoracic)  has  its 
origin  in  the  lower  cord. 

We  must  remember  that  the  nerves  to  the  rhomboids,  to  the  supra- 
spinatus  and  the  infra-spinatus,  to  the  subscapulars  (upper  branch)  and  to 
the  pectoralis  major,  originate  successively  from  the  fifth  and  sixth  cervical 
roots  and  from  the  primary  and  secondary  trunks  following  them.  They 
thus  belong  to  the  higher  root  group. 

The  nerves  to  the  latissimus  dorsi  and  the  teres  major  as  well  as  the 
lower  branch  to  the  subscapularis  originate  in  the  posterior  cord. 

The  lower  trunk  supplies  only  the  nerve  to  the  pectoralis  minor. 

All  the  cervical  roots,  on  leaving  the  intervertebral  foramina,  send  out  a 
communicating  branch  to  the  cervical  sympathetic.  The  branch  from  the 
first  dorsal  root  is  particularly  important,  for  it  carries  to  the  lower  cervical 
ganglion  of  the  sympathetic  the  cilio-spinal  fibres  destined  for  the  innerva- 
tion of  the  pupil. 


LESIONS   OF  THE    BRACHIAL   PLEXUS 

The  brachial  plexus,  like  all  the  nerves,  may  be  affected  directly  by  a 
wound,  compressed  by  a  foreign  body,  a  bony  callus,  a  cicatricial  fibrous 
mass,  or  even  a  simple  hematoma  of  the  supra-clavicular  fossa  or  of  the 
axilla.  But  it  may  also  be  wrenched  by  traction  on  the  upper  limb,  or 
by  violent  downward  traction  of  the  shoulder,  with  or  without  dislocation. 

Wounds  of  the  brachial  plexus  may  affect  the  roots  or  the  primary 
trunks  as  well  as  the  secondary  trunks  and  their  branches  of  division. 

Somewhat  variable  and  often  complex  syndromes  result,  of  which  only 
a  very  summary  description  can  be  given. 

They  differ  mainly  from  the  syndromes  produced  by  wounds  of  the 
peripheral  nerve  trunks  in  the  fact  that  there  is  a  different  distribution 
of  motor  and  sensory  disturbances.  In  the  case  of  the  roots  and  primary 
trunks,  we  have  radicular  distribution  ;  in  the  case  of  le>ion  of  the 
secondary  trunks  we  have  a  distribution  midway  between  that  of  the  roots 
and  of  the  peripheral  nerves. 

We  shall  study  in  succession  : 

1.  The  radicular  syndromes  resulting  from  lesion  of  the  roots  or 
primary  trunks  ;  these  result  from  lesions  above  the  clavicle  and  affecting 
the  nerve  trunks,  either  in  the  supra-clavicular  fossa,  or  between  the  scaleni, 
on  the  sides  of  the  vertebral  column,  or  even  on  a  level  with  the  inter- 
vertebral foramina. 

2.  The  plexus  syndromes  strictly  so  called,  corresponding  to  lesions  of 


BRACHIAL   PLEXUS 


215 


the    secondary    trunks  and  of  their  branches;  these  result  from    lesions 
affecting  the  clavicular  region  or  the  upper  part  of  the  axilla. 

We  have  already  remarked  that  the  roots  and  primary  trunks  are 
frequently  affected  separately,  producing  partial  paralysis  of  the  brachial 
plexus.     The  secondary  trunks,  on  the  other  hand,  closely  adhering  to  one 


Anterior  view. 


Posterior  view. 


Root 
distribution. 


Peripheral 
distribution. 


Root 
istribution. 


Fig.  210. — Root  and  peripheral  sensory  regions. 
The  radicular  sensory  regions  are  indicated  by  horizontal  lines,  parallel  to  the  axis 

of  the  limbs. 


another,  are  more  frequently  affected  as  a  whole  and  often  produce 
complete  paralysis  of  the  brachial  plexus  ;  still,  it  is  possible  to  find  among 
them  syndromes  of  partial  lesion.  On  the  other  hand,  the  close  relations 
of  the  secondary  trunks  with  the  axillary  vessels  explain  the  frequent 
association  of  lesions  and  vascular  syndromes  which  complicate  strikingly 
any  clinical  investigation. 


I.— RADICULAR   SYNDROMES  (ROOTS   AND   PRIMARY   TRUNKS) 

The  general    character   of  the  radicular  syndromes  is  essentially  the 
root  distribution  of  motor  and  sensory  disturbances. 

On  the  other  hand,  however,  a  great  number  of  muscles  are  supplied 


2l6 


NERVE   WOUNDS 


by  two  and  often  three  different  roots  ;  consequently,  partial  paralyses  of 
these  muscles  will  often  be  found. 

Between  the  roots,  too,  there  are  extensive  sensory  substitutions ; 
anaesthesia  therefore  resulting  from  radicular  lesions  is  frequently  less 
obvious  than  anaesthesia  from  lesions  of  the  trunks. 

We  shall  describe  diagrammatically  three  partial  radicular  syndromes, 
corresponding  to  lesions  : 

1.  Of  the  fifth  and  sixth  cervical  roots — upper  radicular  group  comprised 
in  the  upper  primary  trunk. 

2.  Of  the  seventh  cervical  root  and  the  middle  radicular  trunk. 

3.  Of  the  eighth  cervical  root  and  the  first  dorsal — lower  radicular 
group,  comprised  in  the  lower  radicular  trunk. 


I.— UPPER    RADICULAR    GROUP,   FIFTH    AND    SIXTH 
CERVICALS.     (ERB-DUCHENNE   SYNDROME) 

I.  Lesions  of  the  upper  radicular  group  are  characterised  essentially  by 
paralysis  of  the  following  muscles,  supplied  by  its  terminal  branches  ; 


Deltoid. 
Biceps. 

Brachialis  anticus. 
Supinator  longus. 
Muscles  of  the  shoulder. 


Anterior  view.  Posterior  view. 

Fig.  21  1. — Upper  radicular  group.     Motor  topography. 

Deltoid  (circumflex  nerve). 

Biceps  and  brachialis  (musculo-cutaneous  nerve). 

Supinator  longus  (musculo-spiral). 


BRACHIAL    PLEXUS 


217 


We  need  not  insist  on  the  nature  of  these  paralyses,  which  have 
already  been  studied.  We  simply  call  attention  to  the  fact  that  flexion  of 
the  fore-arm  on  the  arm  is  completely  suppressed,  since  the  biceps  and  the 
supinator  longus  are  both  paralysed. 

2.  There  is  also  found  paralysis  of  the  following  muscles  : 

Pectoralis  major  (clavicular  head  only). 

Supra-spinatus  and  infra-spinatus. 

Subscapularis. 


Fig.  212. — Upper  radicular  paralysis  from 
wound  in  the'eervical  region.  Atrophy  of 
muscles  of  the  shoulder,  deltoid,  supra- 
spinatus,  infra-spinatus,  rhomboideus  major 
and  minor,  serratus  magnus  ;  displacement 
of  the  shoulder-blade. 


Fig.  213. — Upper  radicular  paralysis  from 
wrenching  of  the  fifth  and  sixth  cervicals. 
Atrophy  of  shoulder,  of  biceps,  brachial  is 
amicus  and  supinator  longus.  Impossible 
to  flex  the  elbow  or  raise  the  shoulder. 


Teres  major,  the  nerves  of  which  originate  in  the  upper  primary 
trunk  or  its  branches. 

If  the  lesion  affects  the  roots  near  their  origin  we  even  find  paralysis  ot 
the  serratus  magnus,  of  the  rhomboids,  and  the  levator  anguli  scapulae. 

There  results  atrophy  of  all  the  scapular  muscles,  displacement  of  the 
shoulder-blade,  giving  the  appearance  of  winged  scapula  (rhomboids  and 
levator  scapulae)  and  the  almost  absolute  impossibility  of  imparting  to  the 
shoulder-blade  the  balancing  movements  which  might  slightly  compensate 
for  paralysis  of  the  deltoid  (serratus  magnus). 

3.  Finally,  the  upper  radicular  group  partially  supplies  the  following 
muscles  :  coraco-brachial  ;  triceps  ;  radial  extensors  and  supinator  brevis  ; 
pronator  radii  teres  and  flexor  carpi  radialis  ;  the  extensor  ami  flexor 
muscles  of  the  thumb. 


2l8 


NERVE   WOUNDS 


These  muscles  will  be  slightly  weakened. 

4.  Sensory  disturbances,  which  take  place  over  an  area  parallel  to  the 
axis  of  the  limb,  are  never  characterised  by  so  complete  an  anaesthesia  as 
that  of  trunk  lesions.     We  find  a  rather  well-defined  area  of  hypo-aesthesia 

occupying  the  regions  C-5  and  C-6  ;  it 
extends  over  the  outer  surface  of  the  arm 
and  the  fore-arm  ;  it  does  not  reach  the 
hand,  but  at  most  extends  on  to  the  base  of 
the  first  metacarpal. 

The  supinator  jerk,  from  percussion  of 
the  styloid  process,  is  abolished. 

II.— MIDDLE    RADICULAR 
SYNDROME 

Paralysis  of  the  seventh  cervical  or  of 
the  middle  radicular  trunk,  is  essentially 
characterised  by  paralysis  of  the  muscles 
supplied  by  the  musculo-spiral  nerve,  with 
the  exception  of  the  supinator  longus,  which 
is  untouched. 

The  triceps,  weakened,  is  net  completely 
paralysed,  for,  as  we  remember,  it  is  partially 
supplied  by  the  sixth  cervical. 

There    also    persist    some    very    feeble 
movements  of  the  extensors  and  the  extensor 
ossis  metacarpi  pollicis  (supplied   partially  by 
C-6)   and    even    slight   movements    of  the 
extensor  indicis  and  the  extensor  minimi  digiti  (C-6  and  C-8). 

The  syndrome  produced  is  almost  exactly  that  of  saturnine  paralysis 
accompanied  by  similar  integrity  of  the  supinator  longus. 

The  sensory  region  of  the  seventh  cervical  is  extremely  restricted.  It 
comprises  at  the  most  a  small  tract  of  slight  hypo-aesthesia  extending  over 
the  dorsal  surface  of  the  fore-arm  and  the  external  part  of  the  dorsal 
surface  of  the  hand. 

The  olecranon  reflex  is  abolished  or  inverted. 


Fig.  214. —  Upper  radicular  para- 
lysis. Hypo-a^thesia  C-5  and 
C-6. 


III.— LOWER    RADICULAR    GROUP    (ARAN-DUCHENNE 

SYNDROME) 

Lesion  of  the  eighth  cervical  root  and  of  the  first  dorsal  or  of  the 
lower  primary  trunk  is  characterised  by  paralysis  of  the  flexores  digitorum, 
the  flexor  carpi  ulnaris,  the  interossei,  the  thenar  and  hypothenar  eminences. 

Summarising,  we  may  state  that  the  muscles  supplied  by  the  median 
belong  to  the  region  of  the  eighth  cervical,  whereas  the  ulnar  principally 
carries  fibres  of  the  first  dorsal. 


BRACHIAL    PLEXUS 


219 


Triceps  (incom- 
plete). 
Radial  extensors 
Extensors  of 
lingers. 


/!' 


Fig.  215. — Middle  radicular  group  (seventh 
cervical).      Motor  topography. 


Fig.  216. — Middle  radicular  group. 
Sensory  topography. 


FlG.  217. — Middle  radicular  para- 
lysis from  wound  of  the  cervical 
region. 

Considerable  weakening  of  the  tri- 
ceps. Paralysis  of  the  radial  ex- 
tensors and  extensoics  digitorum  ; 
attitude  of  musculo-spiral  para- 
lysis. (Lesion  of  the  seventh 
cervical.) 

In  this  case  the  sixth  cervical  has 
also  been  affected,  for  though  the 
deltoid  is  almost  untouched,  the 
biceps  is  weakened  and  the  supi- 
nator longus  almost  completely 
paralysed,  whereas  it  ought  to  be 
wholly  untouched  in  paralysis 
limited  to  the  seventh  cervical. 

Integrity  of  movements  in  bending 
the  lingers.  Weakening  ot  pro- 
nation and  flexion  of  the  hand 
(pronators,  flexor  carpi  radialis, 
palmaris  longus,  sixth  and  seventh 
cervicals). 

Hypo-aesthesia,  somewhat  more  ex- 
tended in  an  isolated  lesion  of  the 
middle  radicular  trunk,  occupies 
a  track  covering  the  external  pan 
of  the  fore-arm  and  stretching 
forwards  and  backwards  almost 
10  the  middle  line  of  tore  arm  and 


220 


NERVE   WOUNDS 


A  lesion  of  C-8  and  D-i  reproduces  very  nearly  the  appearance  of 
associated  paralysis  of  the  median  and  the  ulnar  with  flattened  hand  or 
simian  griffe,  according  as  we  have  complete  interruption  or  nerve 
irritation. 


Flexores  digitorum. 
Flexor  carpi  ulnaris. 
Muscles  of  the 
hand. 


Motor  topography. 


Sensory  topography. 


Figs.  218  and  219. — Lower  radicular  group  C-8  to  D-i. 


The  muscles  of  the  thenar  eminence,  however,  particularly  the  abductor 
pollicis,  receive  some  fibres  of  C— 7  and  even  of  C-6  ;  the  abductors  of  the 
thumb  seem  to  be  supplied    mainly  by  C-8,  in 
contradistinction  to  the  other  interossei,  for  which 
D-i  seems  predominant. 

Lastly  the  pronator  radii  teres  and  the  flexor 
carpi  radialis  receive,  mostlv  through  the  external 
root  of  the  median,  fibres  coming  from  C-6 
and  C-~.  They  are  largely  unaffected  in  lower 
radicular  paralyses. 

Sensory  disturbances  are  characterised  in  lower 
root  lesions  by  a  band  of  hypo-a?sthesia  of  the 
inner  side  of  the  limb. 

On  the  internal  surface  of  the  arm,  we  note 
the  integrity  of  the  triangular  region  supplied  by 
the  second  and  third  dorsals. 
Into  this  tract  of  hypo-assthesia,  however,  on  the  inner  side  of  the  arm, 


Fig.  220. 
graphy. 
hand. 


-Motor     topo- 
Muscles  of  the 


BRACHIAL    PLEXUS  221 

there  fits  the  triangular  zone  responding  to  the  second  and   third  dorsal 
roots. 

The  ulnar  periosteal  reflex  is  abolished. 


OCULO-PUPILLARY    SYMPATHETIC    SYNDROME 

It  may  be  remembered  that  the  communicating  branch  supplied  to  the 
lower  cervical  ganglion  by  the  first  dorsal  root  carries  to  the  cervical 
sympathetic  the  fibres  of  the  cilio-spinal  medullary  centre. 


Fig.  221. — Lower  radicular  paralysis  from  wound  in  lower  cervical  region,  with  fracture 
of  the  clavicle.  Integrity  of  the  deltoid,  biceps,  supinator  longus,  triceps  and  extensor 
muscles.  Paralysis  and  atrophy  of  the  epitrochlear  muscles  ;  persistence  of  the  move- 
ments of  flexor  carpi  radialis  and  especially  of  the  pronator  radii  teres.  Paralysis  and 
atrophy  of  all  the  muscles  of  the  hand.  The  lesion,  of  a  neuritic  type,  has  determined 
fibrous  contraction  of  the  (lexores  digitorum  and  of  the  palmar  aponeurosis  ;  trophic 
disturbances  of  the  nails. 

If  this  branch  is  destroyed  by  traumatism,  as  is  usually  the  case  in 
the  traumatic  wrenching  of  the  roots,  we  have  the  oculo-pupillary 
syndrome  described  by  Mme.  Dejerine-Klumkc.  This  consists  of  myosis, 
enophthalmos  and  contraction  of  the  palpebral  fissure  of  the  corresponding 
eye.  However,  it  is  not  found  in  the  lower  radicular  lesions  alone  ;  it  may 
be  noticed  after  lesions  higher  up,  affecting  the  upper  cervical  roots.  But 
in   these   cases   it   does   not   come   from    the   radicular  lesion   itself;  it  is 


222 


NERVE   WOUNDS 


produced  by  direct  lesion  of  the  cervical  sympathetic   chain,  affected   by 
traumatism  at  the  same  time  as  the  cervical  roots. 

Total  Radicular  Paralysis 

Total  radicular  paralysis — as  produced  mainly  by  tearing  of  the  brachial 
plexus  owing  to  violent  traction  on  arm  or  shoulder — is  characterised  by 


Fig.  222. — Oculo-pupillary  syndrome  from  lesion  of  the  first  right  dorsal  root 
(Dejerine-Klumplce  syndrome).  Sinking  in  of  the  eye  ;  constriction  of  the  palpebral 
fissure,  myosis. 

complete  paralysis  of  the  upper  limb.  Anaesthesia  is  complete  on  hand  and 
fore-arm,  there  is  sensation,  however,  on  the  upper  part  of  the  shoulder 
(fourth  cervical)  and  on  the  inner  surface  of  the  arm  where  is  found  the 
triangular  zone  supplied  by  the  second  and  third  dorsal  roots. 

The  oculo-pupillary  phenomena  previously  described  (first  dorsal) 
naturally  form  part  of  this  syndrome. 

II.— TRUNK  SYNDROMES   OF  THE   BRACHIAL   PLEXUS 

The  syndromes  produced  by  lesions  of  the  secondary  trunks  and  their 
branches  of  division  closely  resemble  peripheral  syndromes. 

Three  partial  types  may  be  described  : 

i.  Syndrome  of  the  upper  secondary  trunk,  corresponding  to  paralysis 
of  the  musculocutaneous  and  of  the  outer  head  of  the  median. 

2.  Syndrome  of  the  posterior  secondary  trunk  (musculo-spiral  circumflex 
trunk),  characterised  by  complete  paralysis  of  the  circumflex  and  the 
musculo-spiral. 

3.  Syndrome  of  the  lower  secondary  trunk,  corresponding  to  paralysis 
of  the  ulnar  and  of  the  inner  head  of  the  median,  along  with  lesion  of  the 
internal  cutaneous,  and  of  the  lesser  internal  cutaneous. 

As  we  see,  these  syndromes  consist  of  the  associated  paralysis  of  two  or 
more  peripheral  nerves. 


BRACHIAL    PLEXUS 


223 


We  must  lay  stress  on  the  topography  of  the  inner  and  outer  heads  of 
the  median.  In  paralysis  of  the  upper  secondary  trunk  (outer  head  of  the 
median)  we  have  found  complete  paralysis  of  the  pronator  radii  teres  and 
almost  complete  paralysis  of  the  flexor  carpi  radial  is,  accompanied  by 
weakening  of  the  flexor  pollicis  and  of  the  opponens. 

Again,  in  another  case  of  lesion  of  the  lower  secondary  trunk  (inner 
head  of  the  median),  there  was  paralysis  of  the  flexores  digitorum,  with 
preservation  of  some  degree  of  flexion  of  the  thumb  and  of  opposition, 


Fig.  223.  —  Syndrome  of  the  upper 
secondary  trunk  comprising  the  outer 
head  of  the  median. 


Fig.  224.  —  Syndrome  of  lower 
secondary  trunk  comprising  the 
inner  head  of  the  median. 


almost  complete  integrity  of  the  flexor  carpi  radialis  and  complete  integrity 
of  the  pronator  radii  teres. 


The  cases,  moreover,  of  partial  lesion  of  the  brachial  plexus  behind  the 
clavicle  and  at  the  level  of  the  axilla  are  not  very  frequent  ;  more  often  we 
find  important  lesions  affecting  almost  all  the  branches  of  the  plexus.  Still, 
these  branches  are  unequally  affected,  and,  as  time  goes  on,  we  may  find 
that  complete  paralysis  at  the  outset  becomes  dissociated  paralysis  when  the 
less  affected  branches  have  resumed  their  functions. 

Finally,  association  with  vascular  lesions  is  extremely  frequent, 
introducing  into  the  clinical  picture  the  complication  of  more  or  less 
pronounced  symptoms  of  iscluemic  paral}  sis. 


224  NERVE    WOUNDS 

In  this  chapter  we  have  contented  ourselves  with  giving  a  general 
and  systematic  summary  of  the  syndromes  of  the  brachial  plexus.  It  is 
possible,  of  course  to  find  the  most  diverse  associations  ;  we  also  meet  with 
every  clinical  variety  corresponding  to  the  nature  of  the  lesion  :  syndromes 
of  complete  interruption,  of  compression,  nerve  irritation  forms,  or  simple 
neuralgic  syndromes. 

There  is  no  need  to  describe  them  ;  their  characteristics  are  exactly 
the  same  as  those  of  the  various  peripheral  syndromes. 


CHAPTER    XIV 

ISCHEMIC   PARALYSIS  OF  THE   UPPER   LIMB 

Ischemic  paralysis  of  the  upper  limb  is  too  frequently  connected  with 
nerve  wounds,  and  even  when  clearly  defined  is  so  difficult  to  diagnose 
that  we  feel  compelled  to  devote  an  entire  chapter  to  it. 

As  a  rule,  it  follows  obliteration  or  ligature  of  a  large  artery,  e.g. 
subclavian,  axillary  or  brachial  artery.  Nevertheless,  we  have  found 
ischemic  paralysis  following  obliteration  of  the  radial  and  ulnar  arteries,  we 
have  even  met  with  a  very  singular  case,  after  obliteration  of  the  radial 
artery  in  the  anatomic  snuff-box,  accompanied  by  ischemia  of  hand  ami 
fingers. 

Ischemic  paralysis  may  also  be  seen  after  prolonged  contraction  of  the 
upper  limb  ;  plaster  of  Paris  applied  too  tightly  is  the  most  frequent  cause 
of  such  paralysis. 

The  mechanism  of  ischemic  paralysis  caused  by  obliteration  of  an 
arterial  trunk  is  far  from  being  clear.  Only  a  few  obliterations  of  arteries 
are  accompanied  by  ischemic  phenomena.  For  instance,  out  of  thirty-two 
cases  of  ligature  of  the  axillary  and  sub-clavian,  we  have  found  no  more 
than  five  cases  of  genuine  ischemic  paralysis,  some  others  complained  of 
slight  signs  of  ischaemia,  probably  transitory  ;  most  of  them  showed  no 
disturbance  whatsoever. 

In  a  similar  lesion,  such  as  ligature  of  the  axillary,  the  extent  of  the 
ischaemic  region  may  vary  considerably  ;  we  have  seen  paralysis  affect  only 
the  hand  or  rise  as  far  as  the  elbow. 

In  these  cases,  the  integrity  and  distribution  of  the  collateral 
circulation  constitute  an  important  individual  factor.  In  most  cases  tree 
from  paralysis,  we  quickly  observe  the  reappearance  of  the  radial  pulse, 
momentarily  suppressed  by  ligature  ;  the  arterial  blood-pressure  becomes 
almost  normal. 

On  the  other  hand,  we  sometimes  find  cases  where  arterial  anastomoses 
are  lacking,  where  the  radial  pulse  does  not  reappear ;  nevertheless, 
there  are  but  few  ischaemic  phenomena,  or  none  at  all.  For  instance,  we 
have  seen  two  patients  who,  three  months  previously,  had  submitted  to 
ligature  of  the  axillary  ;  in  both  cases  the  radial  pulse  was  suppressed  ; 
both  had  almost  identical  vascular  tension,  viz.  scarcely  any  at  all  ;  and 
yet  the  symptoms  observed  were  totally  different. 

*5 


226  NERVE   WOUNDS 

By  the  Pachon  sphygmomanometer,  the  first  had  a  tension  of  1 7-8  on 
the  healthy  side  ;  of  9-8  with  scarcely  any  oscillations  on  the  ligature 
side  ;  however,  there  was  but  slight  cyanosis  and  cooling  of  the  hand. 

The  second  on  the  healthy  side  had  a  tension  of  22-9  ;  on  the 
paralysed  side  the  tension  was  1 1-9  with  very  faint  oscillations,  though 
perceptibly  stronger  than  in  the  former  case  ;  he  presented  an  instance  of 
complete  ischemic  paralysis  accompanied  by  fibrous  transformation  of  the 
hand. 

Probably  the  elasticity  of  the  vessels,  the  presence  or  absence  of 
atheroma,  the  phenomena  of  vaso-motor  spasms  play  an  important  part  in 
these  cases,  as  well  as  the  nerve  lesions  so  often  associated  with  arterial 
lesions. 

In  addition  to  real  ischaemic  paralysis,  mention  must  be  made  of  the 
more  or  less  obscure  syndromes  of  ischaemia  from  arterial  obliteration  which 
often  accompany  nerve  lesions  :  particularly  lesions  in  the  brachial  plexus 
at  the  level  of  the  axilla  and  wounds  of  the  median  and  ulnar  on  the 
inner  side  of  the  arm. 


CHARACTERISTICS  OF   ISCH/EMIC   PARALYSIS 

We  may  describe  two  phases  in  the  evolution  of  ischaemic  paralysis. 

1.  In  the  first  phase  we  note  cedematous  infiltration  of  the  ischaemic 
regions. 

The  hand  is  cold,  either  simply  cyanosed  or  of  the  reddish  tint  of  the 
lees  of  wine;  it  is  infiltrated  with  a  soft  swelling  which  is  not  confined 
simply  to  the  sub-cutaneous  cellular  tissue,  but  spreads  over  the  muscles, 
giving  them  a  sort  of  pasty  consistence ;  the  skin  is  infiltrated  and 
thickened,  though  remaining  dull  and  dry. 

Movement  is  not  completely  abolished,  and  the  patient  can  still,  though 
with  considerable  trouble,  move  his  fingers  slightly.  Passive  movements 
also  are  still  possible,  although  the  resistance  caused  by  fibrous  transforma- 
tion of  muscles  and  articulations  is  quickly  developed. 

Sensation  has  not  altogether  disappeared  ;  we  even  find,  as  a  rule,  the 
coexistence  of  very  marked  hypo-aesthesia  and  of  painful  hyper-aesthesia  : 
patients  complain  of  a  numbed  feeling  in  the  hand  ;  all  stimuli  of  touch  or 
pain-provoking  heat  are  incompletely  perceived,  badly  localised,  and  above 
all,  imperfectly  differentiated  ;  but  each  of  these  stimuli  gives  rise  to  a 
very  painful  sensation. 

Deep  sensation  is  somewhat  better  retained  than  superficial  sensation. 

Finally,  these  patients  often  complain  of  acute  pains  :  burning  or 
freezing  sensations  with  formication  or  numbness  of  the  hand  ;  deep 
pressure,  cutaneous  stimuli  and  cold  more  especially  intensify  these 
sensations  ;  heat  mostly  calms  them  somewhat,  and  the  patients  carefully 
wrap  the  hand  in  warm  gloves  or  cotton-wool. 


ISCHEMIC   PARALYSIS   OF   THE    UPPER   LIMB     227 

Sensory  disturbances  gradually  increase  from  the  root  to  the  extremity  of 
the  limb,  their  topography  is  therefore  vaguely  segmental. 

2.  In  the  second  phase,  we  see  fibrous  transformation  of  the  infiltrated 
tissues. 

After  a  few  weeks,  oedema 
begins  to  diminish  ;  but  the  sub- 
cutaneous cellular  tissue,  the 
aponeuroses,  the  tendons,  are  gradu- 
ally embedded  in  a  veritable  fibrous 
mass  ;  the  muscles  become  puffy, 
they  harden,  atrophy,  contract  and 
gradually  acquire  a  woody  con- 
sistence. 

The  skin  becomes  smooth  and 
shiny,  of  a  violet  or  even  vivid 
red  colour,  it  is  thin,  dead-looking, 
hard  and  adherent  to  the  subjacent 
tissues;  the  nails  bend  in  like  claws, 
the  fingers  taper  off  and  sometimes 
become  incurved,  following  the 
fibrous  contractions,  the  projections 
of  the  muscular  bellies  disappear. 

After  the  slightest  traumatism  we  may  find  cutaneous  ulcers  of  a  dry 
sloughy  type,  their  cicatrisation  is  often  a  very  long  process. 

All  active  or  passive  movements  disappear  progressively  ;   anaesthesia 


Figs.  225  and  226. — Topography  of  anaes- 
thesia in  two  cases  of  ischemic  paralysis. 


Fie.  227. — Ischaemic  paralysis  following  ligature  of  the  axillary.     Fibrous 

transformation  of  the  hand. 


appears  and  becomes  complete  ;  the  pain  also  calms  down  ;  and  the  hand 
is  gradually  transformed  into  a  sort  of  fibrous,  rigid,  inert  and  insensitive 
appendage. 

In  true  ischemic  paralysis  the  hand  is  habitually  extended]  the  fin 


228 


NERVE    WOUNDS 


slightly  flexed,  but  in  the  case  of  associated  nerve  lesion,  it  maybe  flexed  in 
a  fibrous  griffe,  which  recalls,  in  pronounced  or  distorted  form,  the 
neuritic  griff e  of  the  median  or  the  ulnar. 


Fig.  228. — Ischaemic  paralysis  following  the  crushing  and  obliteration  of  the 
brachial  artery.     Fibrous  transformation  of  the  hand. 

Too  frequently  ischaemic  paralysis  is  incurable,  but  considerable  improve- 
ment may  be  obtained  by  permanent  warm  covering,  hot  baths,  prolonged 
massage  and  mobilisation  and  galvanic  or  faradic  electrical  stimulation. 


Fig.  229.- — Ischaemic  paralysis  from  lesion  of  the  axillary  with  association  ot  nerve  dis- 
turbances.    Fibrous  hand,  completely  immobilised  in  the  position  ot  ulnar  griffe. 


DIAGNOSIS 

Ischaemic  paralysis  is  distinguished  from  nerve  lesions  by  the  following 
characteristics  : — 

I.  Distribution  of  motor  and  sensory  disturbances  corresponding  to  no 
peripheral  nerve  topography.     On  the  contrary,  it  is  segmentary. 


ISCHEMIC    PARALYSIS    OF   THE    UPPER    LIMB      229 

All  these  disturbances  are  pronounced  at  the  periphery  and  gradually 

diminish  towards  the  root  of  the  limb. 

2.  The  special  puffy  or  wooded  consistence  of  all  the  tissues. 

3.  Suppression  of  the  radial  pulse. 

4.  In  some  cases  it  is  even  possible  to  ascertain  that  there  is  no  real 
paralysis  :  a  few  imperfect  movements  continue  for  a  long  time  :   we  find 


Fig.  230. — Ischaemic  paralysis  from  lesion  of  the  brachial  artery. 
Associated  with  median  griff e. 

that  the  muscles  are  not  really  paralysed  but  are  immobilised  by  fibrous 
infiltration. 

5.  Electrical  reactions  likewise  are  somewhat  different  :  there  is  no 
polar  inversion,  but  enormous  hypo-excitability  which  speedily  becomes 
complete  inexcitability  ;  as  long  as  electrical  excitation  is  capable  of  causing 
muscular  contraction,  we  can  obtain  this  movement  by  exciting  the  nerve 
from  a  distance  or  at  the  motor  point,  as  well  as  by  excitation  of  the 
muscle  itself. 


PART    III 
LOWER   LIMB 


CHAPTER  XV 

SCIATIC  NERVE 

The  sciatic  is  by  far  the  most  frequently  affected  nerve  in  the  lower  Limb. 
The  bulk  of  its  trunk,  the  length  of  its  course,  the  number  and  im- 
portance of  its  branches  which  supply  the  greater  part  of  _ 
the  lower  limb,  render  it  particularly  vulnerable. 


ANATOMY   OF  THE    SCIATIC   NERVE 

The  lars:e  sciatic  nerve  is  the  longest  and  most  widelv 
distributed  in  the  human  body. 

It  originates  in  the  fourth  and  fifth  lumbar  roots, 
through  the  medium  of  the  lumbosacral  cord,  and  more 
particularly  in  the  first,  second  and  third  sacral  roots  ;  it 
represents  "  the  sacral  plexus  condensed  in  one  nerve  cord." 
(Cruveilhier.) 

All  its  original  branches  are  united  at  the  level  of  the 
sciatic  notch. 

It  passes  round  the  ischial  spine  and  descends  in  the 
posterior  part  of  the  buttock  between  the  ischium  and 
the  greater  trochanter,  covered  by  the  mass  of  the  gluteal 
muscles  and  the  pyramidalis,  and  also  below  this  muscle 
by  the  lower  part  of  the  gluteus  maximus. 

It  descends  in  the  posterior  part  of  the  thigh  into 
the  interspace  comprised  between  the  semimembranosus 
and  the  semitendinosus  within,  and  the  biceps  without. 
It  rests  on  the  posterior  surface  of  the  femur  which  is 
covered  by  the  insertions  of  the  adductors  and  by  the 
vastus  externus. 

It  becomes  superficial  at  the  upper  end  of  the  popliteal 
space,    in    the    neighbourhood    of  which    it    divides    into 
its    two    terminal     branches — the    external    popliteal    and    the    internal 
popliteal. 

The  level  at  which  this  division  takes  place  is  extremely  variable  ;  it 


232 


NERVE   WOUNDS 


may  be  very  high,  sometimes  these  two  branches  rise  as  far  up  as  the 
pelvis,  distinct  from  each  other  yet  in  close  apposition,  in  gun-barrel 
fashion. 

Collateral  Branches 

Along  its  course,  the  trunk  of  the  great  sciatic  nerve  supplies  : 
i.  The  upper  nerve  to  the  semitendinosus,  which  arises  very  high  up, 
immediately  below  the  tuberosity  of  the  ischium. 


Superior  gluteal  N. 
N.  to  the  pyramidalis 

Inferior  gluteal  N.-l  'i 

Posterior  cutaneous  N.  (per.  br.) 

„         .  ..,,.,  J       WllH  -t^M        It  Great  sciatic  N. 

rostenor  cutaneous  N.  (thigh) 

Nerve  to  the  semitendinosus  ■flBKaBI^/  fl ;     H  N.  to  short  head  of  biceps 

N.  to  the  semimembranosus  '    Iffi/it^Ml  Wsi§k     V   N"  t0  '°ng  head  oi  bicePs 

'Um 'S'/'iBI  JJSH  'wf 
Nerve  to  the  semitendinosus 


Int.  pop.  N. 
N.  to  int.  head  of  gastrocnemius 

Ext.  saph.  N 


Int.  pop.  N. 


xt.  pop.  N. 


N.  to  ext.  head  of  gastrocnemius 


Fig.  232. — Sciatic  nerve  and  its  collateral  branches  in  buttock  and  thigh. 
(After  Sappey.) 

This  is  the  reason  why  the  semitendinosus  is  often  untouched  in  lesions 
of  the  sciatic. 

2.  The  nerve  to  the  long  head  of  the  biceps  which  appears  at  a  very 
variable  level,  most  frequently  in  the  middle  region  of  thigh. 

3.  The  nerve  to  the  semimembranosus  which  originates  at  the  same 
level  and  often  from  the  same  trunk  as  the  nerve  to  the  biceps. 


SCIATIC   NERVE 


233 


Gluteus  maximus' 


Small  sciatic  nerve"  -^ 


[ 


Int.  pop.  N. 

Int.  saph.  N. 
Ext.  popl.  N. 


Int.  saph,  V. 
Ramus  communicans  fibularis 

Int.  head  of  gastrocnemius 

Int,  saph.  N. 


V 


4.  The  nerve  to  the  short  head  of  the  biceps,  the  origin  of  which  also 
varies  considerably,  being  usually  a  little  below  the  nerve  to  the  long  head. 

To  these  collateral 
branches  must  be  added 
another  supplied  by  the 
sciatic  to  the  adductor 
magnus  and  the  upper 
articular  nerve  or  the 
knee. 

There  is  no  need  to 
dwell  on  the  function  of 
these  muscles,  all  being 
flexors  of  the  leg  on  the 
thigh. 

Sufficient  to  note  that 
the  order  in  which  these 
branches  breakaway  from 
above  downwards  ex- 
plains the  frequent  weak- 
ening of  the  biceps  in 
lesions  of  the  sciatic, 
whereas  the  semimembra- 
nosus and  especially  the 
semitendinosus  are  more 
frequently  untouched. 


Terminal  Branches 

The  division  branches 
of  the  sciatic  nerve  really 
constitute  two  distinct 
nerves,  antagonists  of  each 
other  :  the-external  popli- 
teal, the  nerve  of  exten- 
sion, homologous  to  the 
terminal  part  of  the 
musculo-spiral,  and  the 
internal  popliteal,  the 
nerve  of  flexion,  more 
widely  distributed  and 
representing  both  the 
median  and  the  ulnar. 


Int.  saph.  N. 
Ext.  Saph.  N. 

Post.  tih.  N.  (calcaneal  branch)    -- 


Posterior  aspect 

Fig.  233. — Superficial  nerves  of  the  lower  limb.     (Froi 
two  sketches  by  Hirschfeld.) 


I.— EXTERNAL    POPLITEAL   NERVE 

The  external  popliteal  breaks  away  in  the  neighbourhood  of  the  upper 
end  of  the  popliteal  space. 


234 


NERVE   WOUNDS 


It  proceeds  along  the  internal  border  of  the  biceps,  crosses  the  outer 
tuberosity  of  the  tibia  covered  by  the  external  head  of  gastrocnemius,  passes 
behind  the  head  of  the  fibula,  and  goes  round  the  neck  of  this  bone  to 
reach  the  antero-external  region  of  the  leg.  At  this  level  it  is  very  super- 
ficial,  resting   directly   on  the  periosteum  of  the  fibula  where  it  may  be 


Fibular  cut.  br. 


Ext.  pop.  N 

N.  to  tib.  ant 
Ram.  communicans  iibularis 


Anter.  tib.  N. 
Muse  -cut.  N. 
Anter.  tib.  N. 


Ext.  saph. 


Anastom.  of  rami  communi- 
cantes  tibialis  et  Iibularis 

Exter.  saph.  N. 
(terminal  br.) 


Muse.  cut.  N.  (cut.  br.) 


Anastom.  of  ext.  saph.  and 
musculo- cutaneous 
Anastom.  of  ant.  tibial,  and 
musculo-cutaneous 


Fig.  234. — External  popliteal  nerve.     (After  Hirschfeld.) 

involved  in  case  of  fracture  ;  it  is  immediately  covered  by  the  aponeurosis  and 
the  skin. 

It  penetrates  into  the  antero-external  compartment  of  the  leg,  passing 
along  a  musculo-fibrous  canal  formed  by  the  origins  of  the  peroneus  longus. 
Inside  this  canal  it  divides  into  its  two  terminal  branches. 


Collateral  Branches 

After  sending  out  an  articular  branch,  the  external  popliteal  supplies  : 
1.  The  ramus  communicans  fibularis  which  descends  upon  the  posterior 


SCIATIC    NERVE 


2.45 


sur 


u.facc  of  the  external  head  of  gastrocnemius  and  is  distributed  to  the  skin 
of  the  external  and  posterior  region  of  the  leg  and  the  heel.  At  this  level 
it  anastomoses  with  the  external  saphenous  (internal  popliteal). 

2    The  peroneal  cutaneous  branch  or  external  cutaneous  nerve  of  the 
leg   which  appears  at  the  same  level  as  the  former  and  descends  outside  it, 


Ext.  pop.  N, 


Peroneus  longus 


Musculo-cutaneous  N.-- 


Extensor  lonsr.  digitorum  >••-• 


Exter.  saph.  N 41  / 


-Anterior  tibial  N. 


^Tibialis  anticus 


_..,    Extensor  propr.  Iiallucis 


Ant.  tibial  N. 


Fig.  235.— Musculo-cutaneous  nerve  and  anterior  tibial  nerve. 
(After  Hirschfekl,  simplified.) 

distributing  itself  over  the  upper  part  of  the  antero-external   region  of  the 

Terminal  Branches 
1.  Anterior  tibial  nerve.-This  nerve  penetrates  into  the  compartment 

of  the  extensors,  and  descends  at  fust  outside,  then  in  front  of,  and  later 
internal  to  the  anterior  tibial  artery,  it  then  lies  deeply  m  the  muscular 
interspace  that  separates  the   anterior  tibial   on   the  inner    Side   from   the 


236  NERVE    WOUNDS 

extensor  communis,  and  later,  from  the  extensor  proprius  hallucis  on  the 
outer  side. 

At  the  level  of  the  annular  ligament  of  the  ankle,  the  nerve  passes 
beneath  the  tendon  of  the  extensor  hallucis,  appears  on  its  external  border 
and  splits  up  into  its  terminal  branches. 

The  anterior  tibial  nerve  supplies  from  its  collateral  branches  : 

1.  The  tibialis  anticus  by  means  of  two  branches,  superior  and 
inferior. 

2.  The  extensor  communis  digitorum  pedis  ; 

3.  The  extensor  proprius  hallucis. 

At  its  termination,  it  divides  into  two  branches,  external  and  internal. 

The  internal  branch,  more  widely  distributed,  proceeds  along  the  first 
intermetatarsal  space,  covered  by  the  extensor  brevis  digitorum,  and 
anastomoses  in  the  most  variable  fashion,  with  the  terminal  branches  of  the 
musculo-cutaneous. 

The  external  branch  is  divided  into  several  shoots  which  also  proceed 
along  the  second,  third  and  fourth  intermetatarsal  spaces  and  anastomose 
with  the  branches  of  the  musculo-cutaneous. 

It  supplies  the  motor  innervation  of  the  extensor  brevis  digitorum. 

The  anterior  tibial  shares  but  feebly  in  the  sensory  innervation  of  the 
dorsal  surface  of  the  foot.  It  mainly  supplies  articular  and  periosteal  twigs  ; 
its  branches  of  cutaneous  sensibility,  when  they  exist,  are  merged  in  the 
branches  of  the  musculo-cutaneous.  Still,  in  certain  cases,  it  is  possible  to 
meet  with  a  distinct  sensory  region  for  the  anterior  tibial  occupying  the 
dorsal  surface  of  the  first  metatarsal  and  of  the  great  toe,  and  especially  the 
first  inter-metatarsal  space. 

2.  Musculo-cutaneous  nerve. — The  musculo-cutaneous  separates  at  an 
acute  angle  from  the  anterior  tibial,  amidst  the  fibres  of  origin  of  the 
peroneus  longus. 

In  passing  through  this  muscle,  it  reaches  obliquely  the  interspace 
between  the  extensor  communis  on  the  inner  side,  the  peroneus  longus  and 
the  peroneus  brevis  lying  on  the  outer  side. 

It  becomes  superficial  at  about  the  lower  third  of  the  leg. 

In  its  course  the  musculo-cutaneous  supplies  : 

The  peroneus  longus  and  the  peroneus  brevis. 

It  supplies  cutaneous  twigs  to  the  lower  part  of  the  antero-external 
region  of  the  leg. 

It  finally  divides  at  the  lower  third  of  the  leg  into  two  terminal 
branches. 

1.  The  internal  dorsal  cutaneous  nerve  of  the  foot,  which  supplies  the 
internal  collateral  of  the  great  toe. 

The  first  dorsal  interosseous  nerve,  which  produces  the  external 
collateral  of  the  great  toe  and  the  internal  collateral  of  the  second  toe. 

The  second  dorsal  interosseous  nerve,  which  supplies  the  external 
collateral  of  the  second  and  the  internal  collateral  of  the  third  toe. 


SCIATIC   NERVE 


237 


2.  The  middle  dorsal  cutaneous  nerve,  which  supplies  only  the  dorsal 
interosseous  of  the  third  interspace  and  its  two  collateral  branches. 

It  must  be  noted  that  the  fourth  dorsal  interosseous  nerve  comes  from 
the  external  saphenous  (internal  popliteal). 

As  in  the  hand,  the  dorsal  collaterals  do  not  reach  the  extremity  of  the 


Exter.  saph.  N.' 
Inner  head  of  gastrocnemius 

Int.  pop.  N. 
Poster,  tibial.  N. 


Great  sciatic  N. 

Ext.  pop.  N. 
Int.  pop.  N. 

Outer  head  of  gastrocnemius 
to  soleus 

>N.  to  tibialis  posticus 


N.  to  long,  flexor 


r 


N.  to  flexor  longus  hallucis 
N.  to  tibialis  posticus 

N.  to  flexor  longus 


Post,  tibial  N. 
Calcaneal  branch 


-xter.  saph.  N. 


>-' 


Fig.  236. — Internal  popliteal  nerve  and  posterior  tibial  nerve.     (After  Sappey.) 

toes.     The  ungual  phalanx   is  supplied   by  dorsal  branches  coming  from 
plantar  collaterals. 


II.— INTERNAL  POPLITEAL  NERVE  AND  POSTERIOR   TIBIAL 

NERVE 

More  bulky  than  the  external  popliteal,  the  internal  popliteal  nerve  is 
continued  in  the  direction  of  the  trunk  of  the  sciatic. 

It  traverses  the  popliteal  space  and  is  given  off  in  the  angle  formed  by 
the  biceps  and  the  semi-membranosus,  passing  downwards  below  into  the 


238 


NERVE   WOUNDS 


space  between  the  two  heads  of  the  gastrocnemius  and  passes  under  the 
aponeurotic  arch  of  the  soleus.  In  this  course  it  is  in  relation  to  the 
popliteal  vessels  ;  we  then  find  from  without  inwards  and  from  behind 
forwards  the  nerve,  the  vein  and  the  artery.  The  arch  of  the  external 
saphenous  vein  opens  into  the  popliteal  vein,  crossing  the  posterior  and 
internal  surface  of  the  nerve. 


Inter,  pop.  N. 

N.  to  inner  head  of  gastrocnemius 

Exter.  saph.  N. 

Inter,  saph.  N 


Inter,  saph.  N.  (post 


.  far.)-! 


Exter.  saph.  N. 
Inter,  saph.  N 


Post,  tibial.  N.  (calcaneal  br.) 
Exter.  saph.  N.  (calcaneal  br.) 


Ext.  pop.  N. 

Fib.  cut. 

N.  to  exter.  head  of  gastrocnemius 

N.  to  soleus 


Ram.  coram,  fib. 


Anastom.  of  exter.  saph.  and  r. 
coram,  fib. 


Fig.  237. — External  saphenous  nerve  and  ramus  communicans  iibularis. 
(After  Hirschfeld.) 

Starting  from  the  fibrous  arch  of  the  soleus,  the  internal  popliteal  takes 
the  name  of  posterior  tibial. 

The  posterior  tibial  nerve  descends  between  the  superficial  layer  and 
the  deep  layer  of  the  posterior  muscles  of  the  leg.  It  lies  in  the  cellular 
interspaceseparating  the  tibialis  posticus  from  the  flexorcommunisdigitorum  ; 
it  closely  adheres  to  this  deep  muscular  layer  by  means  of  the  deep  or 
sub-solear  aponeurosis  ;  it  is  covered  by  the  soleus  and  afterwards  by  the 
Achilles  tendon. 

The    posterior    tibial     artery,    originating     in     the    popliteal     trunk, 


SCIATIC   NERVE  239 

crosses  the  anterior  surface  of  the  nerve  and  becomes  internal.  Thus  the 
nerve  descends  almost  midway  between  the  posterior  tibial  artery  on  the 
inner  side,  and  the  peroneal  artery  on  the  outer  side. 

At  the  level  of  the  instep,  the  nerve  and  the  posterior  tibial  vessels 
appear  in  the  internal  retro-malleolar  groove  ;  the  nerve  is  behind  the 
artery  and  internal  to  it,  i.e.  deeper  and  more  closely  adherent  to  the  bone 
covered  by  the  tendon  of  the  flexor  longus. 

It  is  in  this  retro-malleolar  groove,  at  the  entrance  of  the  calcanean 
groove  which  forms  its  continuation,  that  the  posterior  tibial  nerve  divides 
into  its  two  terminal  branches,  the  internal  and  the  external  plantar  nerves. 


Collateral  Branches 

I.  In  the  popliteal  space,  the  internal  popliteal  supplies  a  certain 
number  of  muscular  branches  : 

1.  The  nerve  to  the  inner  head  of  gastrocnemius. 

2.  The  nerve  to  the  outer  head  of  gastrocnemius. 

3.  The  nerve  to  the  soleus. 

4.  The  nerve  to  the  plantaris. 

5.  The  nerve  to  the  popliteus  with  muscular  and  vascular  branches 
and  a  branch  to  the  interosseous  membrane. 

6.  It  also  supplies  articular  branches  grouped  by  Cruveilhier  under  the 
name  of  posterior  articular  nerve  of  the  knee. 

7.  Finally,  it  supplies  an  important  sensory  branch,  the  external 
saphenous  nerve  or  tibial  saphenous  which  is  given  off  at  the  upper  or 
middle  part  of  the  popliteal  space,  rejoins  the  external  saphenous  vein  at 
the  upper  part  of  the  leg,  and  descends  with  it  in  the  middle  line,  bein«; 
covered  by  the  superficial  aponeurosis  which  ensheaths  it  in  a  fibrous 
canal. 

At  the  lower  part  of  the  leg,  it  appears  on  the  outer  side  of  the 
Achilles  tendon  and  at  this  level  receives  an  important  anastomosis  from 
the  ramus  communicans  fibularis.  It  finally  reaches  the  outer  edge  of  the 
foot,  describing  a  curve  round  the  outer  malleolus. 

The  external  saphenous  nerve  sends  out  no  sensory  twig  to  the  upper 
part  of  the  leg. 

It  supplies  cutaneous  branches  to  the  lower  part  of  the  leg,  in  the 
malleolar  region  (external  calcanean  nerves)  ;  in  front  of  the  malleolus  it 
anastomoses  with  the  musculo-cutaneous. 

Near  the  tuberosity  of  the  fifth  metatarsal,  it  divides  into  two  terminal 
branches  :  the  outer  one  becomes  the  external  dorsal  collateral  of  the  fifth 
toe  ;  the  inner  one,  the  nerve  of  the  fourth  interosseous  space,  supplies  the 
internal  collateral  of  the  fifth  toe  and  the  external  collateral  of  the  fourth 
toe. 


240 


NERVE    WOUNDS 


2.  At  the  level  of  the  leg   below  the  fibular  arch   of  the  soleus,  the 
posterior  tibial  nerve  which  continues  the  internal  popliteal  supplies  : 
The  tibialis  posticus  ; 
The  flexor  proprius  hallucis  ; 
The  flexor  communis  digitorum. 
It  also  supplies  vascular  branches,  articular  branches  for  the  tibiotarsal 


Inter,  plantar  N. 

Branch  to  accessorius 

Br.  to  adductor  hallucis 

Br.  to  ilexor  brevis 

Ext.  br 
Int.  bi 


Br.  to  abd.  minimi  digiti 
r.  to  accessorius 


Ext.  plantar  N. 


Ext.  plantar  N.  (deep  branch) 
N.  to  add.  min,  dig. 


I  Collate 


ral  to  toes 


Superficial  region. 
Fig.  238. — Plantar  nerves.     (After  Sappey.) 

articulation  and  sensory  branches  of  but  slight  importance  :  the    internal 
supra-malleolar  branch  and  the  internal  calcaneal!  nerve. 


Terminal  Branches 

The  two  terminal  branches,  the  internal  and  external  plantar  nerves, 
reach  the  sole  of  the  foot  by  the  retro-caleanean  groove  and  separate  at  an 
acute  angle,  making  their  way  towards  the  inner  and  outer  sides  of  the  foot. 

They  proceed  between  the  two  muscular  layers  of  the  sole  of  the  toot ; 
covered  by  the  belly  of  the  short  flexors  ;  lying  on  the  accessorius  which 
separates  them  from  the  interossei  and  on  the  tendons  of  the  flexor 
proprius  hallucis  and  the  flexor  communis  digitorum. 

Their  respective  distribution  somewhat  resembles  that  of  the  median 
and  ulnar  in  the  case  of  the  hand. 

1.  Internal  plantar  nerve. — -Apart  from  its  articular  branches,  the 
internal  plantar  nerve  supplies  both  muscular  and  cutaneous  branches. 


SCIATIC    NERVE 


241 


The  muscular  branches  destined  for  the  muscles  are  : 

Abductor  hallucis  ; 

Flexor  brevis  hallucis  ; 

Flexor  brevis  digitorum  pedis  ; 

Accessorius. 

The  cutaneous  branches  arc  of  two  orders.  Firstly,  simple  collateral 
branches  which  perforate  the  plantar  aponeurosis  and  supply  the  plantar 
integuments  from  the  os  calcis  to  the  base  of  the  toes.  These  are  the 
plantar  cutaneous  nerves. 


Int.  plant.  N 


Ext.  hi 
Int.  bi 


N.  to  adduc.  obliq. 

N.  to  interossei 
N.  to  abductor  transversus 


Ex.  plant.  N. 


Superficial  br. 
Deep  br. 


N    to  adductor  transversus 


Deep  dissection  of  the  foot. 
Fig.  239.— Plantar  nerves.     (After  Sappey.) 

Secondly,  terminal  branches,  two  in  number  : 

The  internal  branch  which  supplies  only  the  internal  plantar 
collateral  of  the  great  toe  ; 

The  external  branch  which  supplies  the  first,  second  and  third 
interdigital  nerves  and  the  plantar  collaterals  springing  from  them.  The 
third  interdigital  nerve  receives  from  the  external  plantar  nerve  an 
anastomosis  analogous  to  that  supplied  by  the  ulnar  to  the  median. 

It  is  the  plantar  collaterals  that  supply,  by  means  of  their  dorsal 
branches,  the  dorsal  surface  of  the  ungual   phalanges. 

2.  External  plantar  nerve. — The  external  plantar  nerve  also  supplies 
both  muscular  and  cutaneous  branches. 

1.  By  its  collateral  muscular  branches  it  supplies  the  abductor  minimi 
digiti  pedis  and  the  flexor  brevis  minimi  digiti  pedis. 

Its    deep   terminal    branch    curves    inwards    and    penetrates  the  deep 

16 


242 


NERVE   WOUNDS 


compartment  of  the  sole,  then,  like  the  deep  branch  of  the  ulnar,  it 
proceeds  to  supply  all  the  plantar  interossei,  including  the  adductor 
transversus  and  the  adductor  obliquus  and  all  the  dorsal  interossei,  by 
means  of  its  perforating  branches. 

2.  On  the  other  hand,  the  superficial  terminal  branch  of  the  external 
plantar  is  sensory  ;  it  supplies  : 

The  external  collateral  of  the  little  toe  ; 

The  fourth  interdigital  nerve  with  its  collaterals  ; 

An  anastomosis  to  the  third  interdigital  nerve  (internal  plantar). 

The  plantar  collaterals,  through  their  dorsal  branches,  provide  the  dorsal 
innervation  of  the  ungual  phalanx. 


PARALYSIS   OF   THE   SCIATIC 

Before  studying  paralysis  of  the  sciatic  in  its  entirety,  we  will  study 
separately  the  paralyses  of  each  terminal  branch,  the  external  popliteal  and 
the  internal  popliteal. 

I— PARALYSIS   OF   THE    EXTERNAL  POPLITEAL 

Motor  Syndrome 

The  external  popliteal  supplies  the  muscles  of  the  antero-external 
compartment  of  the  leg  : 

The  tibialis  anticus  ; 

The  extensor  longus  digitorum  pedis  ; 

The  extensor  proprius  hallucis  ; 

The  extensor  brevis  digitorum  is  supplied  by  the 
anterior  tibial  ;  the  peroneus  brevis  and  the  peroneus 
longus  are  supplied  by  the  musculo-cutaneous. 

Paralysis  of  this  nerve  is  indicated  by  suppression  of 
the  elevation  and  extension  movements  of  the  foot  * 
and  of  the  toes,  by  the  abolition  of  internal  rotation 
and  of  elevation  of  the  internal  border  of  the  foot, 
movements  produced  by  the  tibialis  anticus  ;  by  the 
loss  of  external  rotation,  of  abduction  and  of  elevation  of 
the  external  border  of  the  foot,  movements  produced 
by  the  peroneal  group. 

To  those  main  disturbances  is  added  the  collapse  of 

the  arch  of  the  foot  normally  maintained  by  the  tendon 

of  the  tibialis  anticus  and  of  the  peroneus  longus.     The 

Fig.  240. — Muscles   tibialis  posticus   (internal  popliteal)  supports  and   raises 
supplied     by    the         .        .  r    ,         ,  , 

external  popliteal.   onv  tne  inner  portion  or  the  plantar  arch. 

*  Wc  use  the  expression  "extension  of  the  foot  "  for  the  dorsal  raising  of  the  foot,  comparing 
it  with  the  synergic  movement  of  raising  or  extending  the  toes,  and  from  analogy  between  the 
functions  of  the  extensor  of  hand  and  fingers,  and  the  external  popliteal. 

By  flexion  of  the  foot  we  mean  the  movement  of  lowering  the  toes,  analogous  with  flexion  of 
the  hand. 


SCIATIC    NERVE 


243 


This  paralysis  results  in  a  drooping  of  the  foot  with  the  toes  pointing 
towards  the  ground,  and  in  a  characteristic  gait  :  steppage. 


Fin.  241. — Paralysis  of  the  external  popliteal.      Atrophy  of  the  antero-external 
group.     Foot-drop,  with  dorsal  tumour  of  the  tarsus. 


The  toes  are  flexed  from  the  loss  of  the  antagonism  of  the  extensors. 

As  Pitre  and  Testut  have  observed,  we  may  easily  detect  the  existence 
of  paralysis  of  the  external  popliteal 
by  asking  the  patient,  who  is  seated, 
to  raise  his  toes  and  keep  them 
clear  of  the  ground,  the  heel  re- 
maining on  the  ground. 

Paralysis  of  the  external  popli- 
teal is  easy  to  recognise.  Later 
on  we  shall  see  what  are  the  possible 
errors  in  diagnosis. 

Here  we  will  mention  only  one 
of  these  :  the  possibility  of  attri- 
buting to  the  tibialis  anticus  the 
slight  power  of  adduction  possessed 
by  the  tibialis  posticus,  either  volun- 
tary or  resulting  from  electrical 
stimuli.  To  avoid  this  error,  it  is 
sufficient  to  raise  the  foot  and  keep 
it  at  right  angles  ;  in  this  position 
the  smallest  contractions  of  the 
tibialis  anticus  are  indicated  both 
by  adduction  and  by  raising  the 
foot ;  there  is  distinctly  perceived 
beneath  the  skin  the  rising  of  the 
tendon  :  adduction  movements  without  raising  the  foot  are  produced  by  the 
tibialis  posticus. 


242. — Steppage  in  paralysis  of  the 

external  popliteal. 


244 


NERVE   WOUNDS 


Sensory  Syndrome 


The  complete  sensory  d 
I 


A 


V 


Figs.  243  and  244. — Sensory 
distribution  of  the  external 
popliteal,  comprising  :  the 
peroneal  cutaneous  branch 
(external  surface  of  the  leg)  ; 
the  ramus  communicans 
fibularis  (posterior  surface)  ; 
the  anterior  tibial  and  the 
musculo-cutaneous  (dorsal 
surface  of  the  foot). 


istribution  of  the  external  popliteal  comprises  a 
broad  tract  occupying  the  entire  antero- 
external  surface  of  the  leg  and  a  part  of  its 
posterior  surface  ;  it  spreads  over  the  dorsal 
surface  of  the  foot  with  the  exception  of  the 
internal  and  external  borders  and  the  ungual 
phalanges. 

In  this  sensory  distribution  several  zones 
must  be  distinguished. 

The  antero-external  surface  of  the  leg  is 
supplied  by  the  peroneal  cutaneous  branch, 
the  posterior  part  by  the  ramus  communicans 
fibularis  ;  the  musculo-cutaneous  is  distributed 
only  over  the  lower  region  of  the  leg  and  the 
dorsal  surface  of  the  foot.  To  this  latter 
region  are  confined  the  sensory  disturbances 
observed  when  the  lesion  of  the  external 
popliteal  is  below  the  first  two  branches  ;  this, 
indeed,  frequently  happens,  for  the  ramus 
communicans  fibularis  and  the  peroneal 
cutaneous  branch  have  their  origin  rather 
high  in  the  upper  region  of  the  popliteal 
space. 

Moreover,  we  must  not  expect  to  find 
complete  anaesthesia  ;  it  is  not  constant,  and 
when  it  exists  is  to  be  found  only  at  the 
middle  of  the  external  surface  of  the  leg  and 
on  the  dorsal  surface  of  the  foot. 


Trophic  and  Vaso-Motor  Syndrome 

Occasionally  we  find  dorsal  oedema  of  the  foot,  pallor  or  cyanosis  of  the 
integuments  ;  cutaneous  desquamation,  hypertrichosis. 

In  some  cases  we  have  found  traumatic  ulcers  on  the  back  of  the  foot, 
produced  by  the  boot  ;  their  extremely  slow  cicatrisation  is  a  sign  of 
trophic  disturbances. 

Finally,  if  foot-drop  is  considerable  and  hypotonia  prolonged,  we  may 
observe  a  sort  of  tumour  on  the  dorsum  of  the  tarsus,  comparable  with  the 
dorsal  tumour  of  the  carpus  in  musculo-spiral  paralysis. 

As  a  rule,  however,  trophic  and  vaso-motor  disturbances  of  the 
external  popliteal  are  of  slight  importance,  the  result  of  substitution  by  the 
internal  popliteal. 


SCIATIC    NERVE 


245 


I.— CLINICAL   FORMS   OF   PARALYSIS   OF   THE   EXTERNAL 

POPLITEAL 

As  in  the  case  of  all    nerve   trunks,   we  may  find    the  syndrome  of 
complete  interruption  or  of  simple  compression. 
The    syndrome    of  com- 


plete  interruption    is    charac- 
terised : 

By  complete  and  rapid 
loss  of  muscular  tone,  intensi- 
fying the  foot-drop  ; 

By  rapid  muscular 
atrophy  ; 

By  the  localisation  of  the 
resulting  formication  to  a 
definite  area  ; 

By  permanence  and  fixity 
of  anaesthesia  as  well  as  by 
the  absence  of  paresthetic 
zones. 

In  the  syndrome  of  com- 
pression we  note  the  opposite 
characteristics,  particularly  the 
prolonged  persistence  of  mus- 
cular tone. 

If  nerve  regeneration  takes 
place,  we  follow  the  pro- 
gression of  formication  along 
the  paralysed  nerves  simul- 
taneously with  the  reappear- 
ance of  muscular  tone. 

We  may  also  meet  with 
syndromes  of  nerve  irritation, 
with  cutaneous  trophic  dis- 
turbances, tendon  adhesions, 
scaly  desquamation,  pain  by 
pressure  on  muscles  and  nerve 
trunks,  muscular  fibrous  con- 
tractions which  limit  the 
passive  flexion  of  foot  and  toes 
and  consequently  diminish 
steppage. 


Before  the 

operation. 


The  95th  day 
after  suture  of 
the  nerve. 
b 


Fig.  245. — Attitude  of  the  right  foot  when  walking, 
before  and  after  nerve  suture  in  a  case  of  para- 
lysis of  the  external  popliteal  with  syndrome  of 
complete    interruption    in    section    of  the    nerve 

by  shell  splinter  (Captain  C ).     a.  Muscular 

atony  and  droop  of  foot  and  basal  phalanges  of 
toes  before  nerve  suture  ;  foot  swinging,  equino- 
varus,  dorsal  swelling  of  the  metatarsus.  Photo- 
graph taken  on  the  66th  day  after  the  wound. 
/>.  Return  of  tone  showing  attitude  of  the  foot 
on  the  95th  day  after  suture  of  the  nerve;  the 
foot  is  no  longer  swinging,  walking  is  easier, 
running  is  possible,  pes  euuinus  less  pronounced, 
the  varus  has  almost  disappeared  ;  the  basal 
phalanges  are  no  longer  drooping  but  extended 
on  the  metatarsals  ;  dorsal  swelling  of  the  meta- 
tarsus has  disappeared.  So  far  there  is  neither 
elevation  movement  of  foot  nor  extension  move- 
ment of  the  first  phalanx  of  the  toes,  but  in  the 
horizontal  position  the  Captain  can  carry  out 
very  marked  abduction  of  the  foot  accompanied 
by  elevation  of  its  external  edge  (contraction  of 
the  peroneals).  (J.  and  A.  Dejerine  and  Mouzon. 
Presse  Medicate,  10  May,  191  5.) 


These    neuritic,    or    even 
simple  neuralgic  syndromes,  however,  are  somewhat  rare. 


The  external 


246 


NERVE   WOUNDS 


popliteal,  like  the  musculo-spiral,  and  in  contradistinction  to  the  internal 
popliteal,  is  not  a  very  sensitive  or  painful  nerve. 


14th  November,  before 

the  operation. 

a  b 


1 6th  December,  20th  day 

after  suture  of  nerve. 

a  b 


2nd  March,  97th  day 

after  suture  of  nerve. 

a  b 


A  B  C 

Fig.  24.6. — State  of  sensibility  to  pin-prick  before  and  after  suture  of  the  nerve  in  a  case 

of  paralysis  of  the  external  popliteal  by  complete  section  of  the  nerve  (Captain  C ). 

Note  in  B  the  appearance  of  a  small  zone  of  paresthesia  on  the  dorsal  surface  of  the 
first  interosseous  space.  Black:  pricking  causes  no  sensation.  Horizontal  hatching: 
pin-prick  is  felt  simply  as  contact.  Oblique  hatching :  diminished  sensibility  to  touch 
and  pin-prick.  Oblique  hatching  with  points  and  crosses :  hypo-sesthesia  with  inter- 
mittent hyperesthesia  ;  the  crosses  indicate  delayed  persistent  sensations,  with  diffusion, 
irradiations  and  errors  of  identification,  the  points  indicate  that  the  sensation  of  pin- 
prick is,  in  addition,  particularly  disagreeable  (paresthesia).  (J.  and  A.  Dejerine  and 
Mouzon.     Presse  Medicate,  10  May,  19 15.) 

Finally  the  external  popliteal  may  be  affected  by  dissociated  lesions  and 
partial  paralysis. 

We  will  relate  two  instances  of  these. 


Exter.  pop. 
Orifice  of  bullet. 


Fig.  247.— Dissociated  paralysis  of  the  external 
popliteal  affecting  solely  the  fibres  of  the 
anterior  tibial. 


FlG.  248. — Sensory  distribution  of 
the  anterior  fibres  of  the  external 
popliteal  (same  case  as  Fig.  247). 


SCIATIC    NERVE 


247 


In  the  first  case  a  bullet  had  struck  the  anterior  part  of  the  external 
popliteal,  behind  the  head  of  the  fibula.  The  muscular  group  of  the 
anterior  tibial  was  paralysed  ;  the  peroneal  muscles  were  not  affected. 
The  internal  part  of  the  distribution  of  the  musculo-cutaneous  was  devoid 
of  sensation. 

In  another  case,  a  small  shell  splinter,  embedded  in  the  external  and 
posterior  part  of  the  external  popliteal,  almost  at  the  same  level,  caused 
paralysis  accompanied  by  nerve  pains  in  the  peroneal  muscles  alone, 
together  with  hyperesthesia  of  the  external  part  of  the  cutaneous  dis- 
tribution. 

We  may  therefore  conclude  that,  behind  the  head  of  the  fibula,  the 
fibres  destined  for  the  anterior  tibial  are  in  front,  the  fibres  of  the  peroneals 
are  behind.  In  the  thigh,  the  fibres  destined  for  the  tibialis  anticus  form 
the  most  external  group  of  the  external  fasciculi  of  the  sciatic  nerve  which 
represent  the  external  popliteal.  This  position  corresponds  to  the  very  high 
root  origin  of  the  nerve  fibres  to  the  tibialis  anticus  (fourth  lumbar). 

II.— PARALYSIS   OF  THE   ANTERIOR   TIBIAL   NERVE 

The  anterior  tibial  nerve  may  be  affected  separately  after  bifurcation 
of  the  external  popliteal. 

Its  paralysis  exactly  reproduces  the  type  of  dissociated  paralysis  which 
we  have  just  been  studying. 


FlG.  2+9. — Paralysis  of  the  anterior  tibial  nerve.     Foot-drop  with  steppage.     Integrity 

of  the  musculo-cutaneous.  Retention  of  lateral  movements  by  the  action  oi  the 
peroneals.  Faradic  excitation  of  the  external  popliteal  nerve  causes  only  the  projection 
of  the  peroneal  tendons,  without  raising-  of  the  foot  and  the  toes. 

The  extensors  and  the  tibialis  anticus  are  paralysed,  whereas  the 
peroneals  are  untouched. 

Cutaneous  anesthesia  is    almost   absent  ;    the    anterior  tibial    is    but 

slightly  sensory,  it  possesses   no    distinctive    region    of    its  own,    for    its 


248 


NERVE    WOUNDS 


cutaneous  branches  anastomose  with  the  branches  of  the  musculo- 
cutaneous. Its  terminal  branches  are  more  specially  articular  and 
periosteal,  comparable  to  the  terminations  of  the  posterior  branch  of 
the  musculo-spiral.  At  most  there  is  slight  hype- 
resthesia of  the  dorsal  surface  of  the  foot,  more 
pronounced  near  the  inner  edge,  and  more  especially 
a  small  triangular  region  of  anaesthesia  behind  the  first 
interdigital  space. 

The  anterior  tibial  nerve  may  also  be  affected 
below  the  branches  destined  for  the  tibialis  anticus  and 
the  extensor  longus. 

Here  we  have  isolated  paralysis  of  the  extensor  of 
the  great  toe,  which  remains  flaccid  and  half  flexed, 
whilst  the  other  toes  can  easily  be  raised. 

Finally,  paralysis  of  the  external  popliteal  and  of 
the  anterior  tibial  is  always  accompanied  by  paralysis 
of  the  extensor  brevis  digitorum  muscle  which  is  sup- 
plied by  the  anterior  tibial  nerve  ;  it  is  recognised  mainly 
by  flaccid ity  of  the  muscle  and  disappearance  of  its 
faradic  contractions ;  for  after  all  the  accessorius  is  but  an 
accessory  synergic  muscle  of  the  extensors  of  the  toes. 


Fig.  250. — Sensory 
distribution  of  the 
anterior  tibial. 


Fig.  251. — Isolated  paralysis  of  the  extensor  of  the  great  toe,  caused  by  lesion  of  the 
anterior  tibial  at  the  middle  of  the  leg.  The  patient  can  easily  raise  the  other  four 
toes. 


III.-ISOLATED   PARALYSIS   OF   THE   MUSCULO  CUTANEOUS 

Isolated  lesion  of  the  musculo-cutaneous  nerve  is  shown  by  paralysis 
of  the  peroneals,  with  loss  of  abduction,  of  rotation  outwards  and  of  eleva- 
tion of  the  external  edge  of  the  foot. 

Raising  the  foot  is  still  possible  by  means  of  the  extensors  ami  the  tibialis 


sciatic  np:rve 


249 


anticus,  but,  since  antagonism  of  the  peroneals  is  lacking,  they  are  accom- 
panied by  a  rotation  inwards,  by  adduction  and  elevation  of  the  inner  edge, 
effected  by  the  tibialis  anticus.  If  there  is  considerable  hypotonia  of  the 
peroneals,  paralytic  talipes  varus  may  result,  and  the  patient  walks  on  the 
outer  edge  of  the  foot. 

The  musculo-cutaneous  nerve  is  sometimes  affected  below  the  peroneals, 

in  its  sensory  part.  This 
lesion  is  indicated  solely  by 
anaesthesia  of  the  cutaneous 
area  which  comprises  almost 


Fig.  252. — Isolated  paralysis  of  the  musculo- 
cutaneous, producing,  on  the  left,  a  deviation 
of  the  foot  inwards  (paralytic  talipes  varus). 


Fig.  253. — Sensory  dis- 
tribution of  the  mus- 
culo-cutaneous. 


the  entire  sensory  distribution  of  the  external  popliteal  on  the  dorsal 
surface  of  the  foot,  with  the  exception  of  the  small  interdigital  triangle  of 
the  first  interspace  specially  supplied  by  the  anterior  tibial. 

It  sometimes  happens  that  the  pain  caused  by  pressure  on  a  terminal 
neuroma  or  by  confinement  of  the  nerve  in  a  cicatrix,  or  even  by  simple 
formication  of  regeneration  in  the  neuroma  and  the  branches  of  the  nen  es, 
renders  the  wearing  of  boots  or  shoes  and  especially  of  leggings  painful. 

We  have  noted  several  cases  of  somewhat  severe  neuralgia  of  the  mus- 
culo-cutaneous, injured  in  the  middle  or  the  lower  part  of  the  leg  ;  one 
particularly  painful  case  even  necessitated  resection  of  the  neuroma  and 
embedding  of  the  central  end  deep  in  the  tissues. 


250 


NERVE   WOUNDS 


II.— INTERNAL    POPLITEAL   AND    POSTERIOR   TIBIAL 


I.— INTERNAL   POPLITEAL 


Motor  Syndrome 

Lesions  of  the  internal  popliteal  produce  paralysis  of  all  the  posterior 
muscles  of  the  leg  and  of  all  the  plantar  muscles. 

There  results  disappearance  of  the  movements  that  produce  flexion  or 

lowering  of  the   foot   (gastrocnemius    and 
soleus)  — 

Abolition  of  flexion  of  the  toes  by  the 
muscles  : 

flexor  longus  hallucis, 
flexor  longus  digitorum, 
flexor  brevis  digitorum. 
Collapse  of  the  plantar  arch,  in  its  inner 
part   (tibialis  posticus)   together  with  con- 
siderable weakening  of  rotation  and  adduc- 
tion movements,  incompletely  carried  out 
by  the  tibialis  anticus. 

Loss  of  adduction  and  abduction  of  the 
toes  (adductors  and  abductors  of  the  first 
and  fifth  toe,  dorsal  and  plantar  inter- 
ossei). 

Nevertheless,  at  first,  walking  does  not 
appear  to  be  greatly  impeded.  Paralysis 
of  the  internal  popliteal  may  pass  unnoticed 
on  a  superficial  examination. 

All  we  see  is  that  the  patient  puts  his 
foot  flat  down  ;  that  he  does  not  lift  the 
that  he  cannot  rise 
on  his  toes. 


Fig.  254.  Fig.  255. 

Fig.  254. — Muscles  supplied  by 
the  internal  popliteal.  Super- 
ficial layer,  gastrocnemius,  soleus, 
plantaris. 

Fig.  255. — Deep  layer.    Popliteus. 

Tibialis  posticus.     Flexor  longus     heel    from  the  ground 
digitorum.        Flexor       proprius 
hallucis.     These  last  three  mus- 
cles are  supplied  by  the  posterior  The   patient,  when  seated,  is  unable  to 
tibial  below  the  fibrous  arch  of    raise  his  heel  by  using  his  toes  as  a  fulcrum. 

(Pitres  and  Testut.) 
The  internal  plantar  arch  is  flattened  out,  being  deprived  of  the  support 

of  the  tibialis  posticus,  whilst  the  antagonism  of  the  peroneals  on  the  other 

hand  raises  the  outer  edge.     The  patient  thus  walks  on  a  sort  of  splay-foot, 

heavily,  without  elasticity  or  spring,  and  with  a  degree  of  uneasiness  which 

is  rapidly  increased  by  fatigue  of  the  antagonists. 

At  rest,  the  foot  is  extended,  passive  hyper-extension  appears  and  may 

become  extreme,  as  soon  as  the  tone  of  the  muscles  of  the  calf  disappears. 


the  soleus. 


SCIATIC   NERVE 


251 


The  toes  are  in  simple  extension  or  even  in  hyper-extension,  according 
as  the  tone  of  the  flexors  and  interrossei  persists  or  not. 

When  the  patient  attempts  to  raise  and  stretch  his  toes,  we  sometimes 
find  a  curious  attitude  of  extreme  hyper-extension  of  the  toes,  caused  by  the 


Fig.  256. — Paralysis  of  the  internal  popliteal.     Hyper-extension  of  the  toes  by  contrac- 
tion of  the  extensors  and  loss  of  tone  of  flexors  and  interossei. 

predominating  action  of  the  extensors  deprived  of  the  antagonistic  tone  of 
the  flexors  of  the  toes  and  of  the  interossei. 

Both  the  Achillean  reflex  and  the  plantar  reflex  have  disappeared. 

Sensory  Syndrome 

The  sensory  region  comprises  the  entire  plantar  surface  ;  the  back  and 
lower  part  of  the  leg  vip  to  about  the  middle  third  ;  the  outer  edge  of  the 
foot  and  the  outer  part  of  its  dorsal  surface  limited  by  a  line  which  joins 
the  third  interdigital  space  ;  the  dorsal  surface  of  the  last  phalanx  of 
the  toes. 

If  the  trunk  of  the  sciatic  is  injured  below  the  origin  of  the  external 
saphenous,  the  external  edge  of  the  foot  and  the  part  close  to  its  plantar 
surface  naturally  retain  their  sensibility. 


Trophic  and  Vaso-motor  Syndrome 

In  simple  paralysis,  as  the  result  of  compression  or  complete  inter- 
ruption, trophic  and  vaso-motor  disturbances  are  almost  entirely  absent. 
It  is  seldom  that  we  find  cyanosis  of  the  toes  or  pronounced  cutaneous 
disturbances;  plantar  hvper-hydrosis,  however,  is  somewhat  frequent  ;  the 


252 


NERVE   WOUNDS 


frequency  of"  chilblains  on  the  toes  is  also  to  be  noted,  as  is  the  readiness 
with  which  mechanical  ulcers  appear  on  the  plantar  surface. 

We  have  several  times  found  superficial  sores  of  this  kind,  caused  by 
injuries  from  the  boots,  at  the  level  of  the  metatarso-phalangeal  articulations. 

In  neuritic  types,  however,  trophic  disturbances  are  very  great,  affecting 
the  skin,  the  muscles  and  the  plantar  aponeurosis  ;  they  also  affect  the  toe- 
nails which  are  not  touched  by  the  external  popliteal. 


Fig.  257.         Fig.  258.  Fig.  259.  Fig.  260. 

Figs.  257,  258,  259,  260. — Sensory  area  of  the  internal  popliteal  comprising  :  the 
external  saphenous  ;  external  surface  of  the  instep  {horizontal  hatching),  outer  edge  of 
the  foot,  dorsal  surface  of  the  foot  to  the  third  intermetarsal  space.  The  posterior 
tibial,  cutaneous  branch  (oblique  hatching).  The  external  ami  internal  plantars  [crossed 
hatching)  which  supply,  on  the  dorsal  surface,  the  last  phalanx  of  the  toes. 

In  the  case  of  the  internal  popliteal  we  may  say  the  same  as  for  the 
external  ;  trophic  and  especially  vaso-motor  disturbances  are  less  pro- 
nounced in  isolated  paralysis  of  this  nerve  than  in  complete  paralysis  of 
the  sciatic.  Probably  they  are  modified  by  substitution  of  the  external 
popliteal. 

Clinical  Types 

We  meet  with  both  compression  and  interruption  types  in  lesions  of  the 
internal  popliteal.  Interruption  types,  moreover,  are  by  far  the  more  fre- 
quent ;  there  is  no  need  to  insist  on  the  characteristics  by  which  they  are 


SCIATIC    NERVE 


253 


to  be  recognised  :  early  hypotonia  and  atrophy,  fixity  of  sensory  disturb- 
ances, clearness  of  RD,  fixed  location  of  formication,  insensibility  to  pain 


Fig.  261. — Ulcers  on  the  sole  of  the  foot  in  a  case  of  interruption  ot  the  posterior  tibial. 


by  pressure  on  the  muscles  of  the  calf  and  on  the  muscle  masses  in  the  sole 
of  the  foot,  as  well  as  on  the  nerve  along  its  entire  distribution. 

In  contradistinction  to  the  ex- 
ternal popliteal,  the  internal  popliteal 
is  frequently  the  seat  of  neuritic  or 
neuralgic  lesions  capable  of  repro- 
ducing all  the  syndromes  of  irritation 
studied  in  the  case  of  the  upper  limb. 

The  slight  neuritic  type,  often 
without  complete  paralysis,  though 
accompanied  by  pain  on  pressure  on 
the  nerves  and  muscular  bellies, 
always  causes  slight  fibrous  contrac- 
tion of  the  Achilles  tendon  gradu- 
ally producing  a  certain  degree  of  pes 
equinus. 

The  grave  neuritic  types  are 
rather  frequent,  accompanied  by  in- 
tolerable pains,  suppressing  sleep  and 
necessitating  the  use  of  morphine  ; 
pressure  on  the  nerve  trunks,  and 
especially  on  the  muscles  of  the  calf 
and  on  the  plantar  muscles,  causes 
violent  pains. 

Trophic    disturbances    are     very 


Fig.   2^2.     Fibrous   contraction    <>t    the 
call   and   pes  equinus  caused   by  slight 

neuritic   lesion  of  the   internal    popliteal 
at  the  upper  par)  of  the  popliteal  space. 


marked.     Along  with  scaly  desquamation,  fibrous  infiltration  ot  the  skin, 


254  NERVE    WOUNDS 

and  the  claw-like  curve  of  the  nails,  we  find  that  grave  deformities 
supervene. 

Fibrous  contraction  of  the  calf  soon  immobilises  the  foot  in  a  state  of 
forced  flexion,  suppresses  the  movements  of  the  antagonistic  extensors  and 
very  often  renders  necessary,  after  cure  of  the  neuritis,  tenotomy  of  the 
Achilles  tendon.  Contraction  of  the  plantar  muscles  and  of  the  plantar 
aponeurosis  along  with  formation  of  fibrous  cords  and  nodes,  ends  in  the 
claw-like  attitude  of  the  foot,  and  will  necessitate,  for  a  few  months  after 
cure,  both  massage  and  mobilisation  of  the  foot,  sometimes  even  surgical 
section  of  the  aponeurotic  fibres  and  of  the  contracted  flexor  tendons. 

Neuritis  of  the  internal  popliteal,  when  intense,  is  a  very  serious  type, 
capable  of  producing  irreducible  deformities  ;   it  is  certainly  more  serious 


Fig.  263. — Fibrous  contraction  of  the  calf  and  pes  equinus.  Contraction  of  the  flexors 
and  of  the  plantar  aponeurosis,  producing  fibrous  griffe  of  the  toes — neuritis  of  ,the 
internal  popliteal. 

in  its  consequences  than  section  of  the  nerve.  Consequently,  in  two 
particularly  serious  cases,  we  did  not  hesitate  to  practise  resection  of  the 
lesion  and  suture  of  the  nerve.  Six  weeks  afterwards,  these  two  patients 
were  walking  without  a  stick,  though  there  was  paralysis  of  the  internal 
popliteal  ;  the  immediate  disappearance  of  the  pains  had  permitted  of 
massage  and  mobilisation  of  the  limb,  thus  effecting  a  cure  without  trophic 
disturbances  or  fibrous  contractions. 

The  simple  neuralgic  type,  accompanied  by  pain  on  pressure  on  the 
nerve  trunks  and  also  plantar  hyperesthesia,  is  serious  only  because  of 
the  very  long  time  it  takes  to  cure. 

Neuralgia  of  the  internal  popliteal  frequently  assumes  the  type  of 
causalgia.  Next  to  the  median,  this  is  the  nerve  most  frequently  affected. 
In  these  cases,  we  find  the  same  absence  of  paralysis  ;  trophic  and  vaso- 
motor disturbances  are  still  less  pronounced  ;  but  the  pains  are  often 
terrible.     These    are    the  special  violent   pains  affecting  the  entire  limb 


SCIATIC   NERVE  255 

with  a  burning  sensation,  caused  by  the  slightest  cutaneous  touch  far  more 
than  by  deep  pressure,  above  all,  provoked  by  the  most  trifling  emotions. 

Partial  lesions  of  the  internal  popliteal  produce  dissociated  syndromes 
which  enable  us  to  set  up  the  following  fascicular  topography  ;  we  find, 
from  within  outwards,  the  external  saphenous  nerve,  then  the  plantar 
nerves,  the  nerve  to  the  inner  head  of  gastrocnemius  ;  then  further  out 
are  the  fibres  to  the  tibialis  posticus,  to  the  flexor  longus  digitorum  pedis, 
the  calcanean  branches  and  the  superficial  branch  of  the  external  plantar 
nerve.      (J.  and  A.  Dcjerinc  and  Mouzon.) 

II.— PARALYSIS   OF  THE   POSTERIOR   TIBIAL   NERVE 

From  the  fibrous  arch  of  the  soleus  onwards  the  internal  popliteal 
assumes  the  name  of  posterior  tibial.  This  nerve  is  very  often  affected  by 
traumatisms  in  the  calf  or  perforating  wounds  in  the  leg,  though  paralysis 
of  the  nerve  is  frequently  overlooked.  Indeed,  the  gastrocnemius  and 
the  soleus,  supplied  by  the  internal 
popliteal,  have  retained  their  move- 
ments j  the  muscles  of  the  deep 
layer,  tibialis  posticus,  flexor  com- 
munis digitorum  pedis  and  flexor 
■  proprius  hallucis,  which  receive 
their  branches  from  the  posterior 

tibial    at    the    upper    part    of   the 

,  „  ,      .       „-..  FlG.  264. — Anaesthesia  caused  by  lesion  ot 

leg,  are  usually  untouched.     Thus,  the  posterior  tibial. 

all  disturbances  are  practically  re- 
duced to  paralysis  of  the  plantar  muscles  and  partial  anaesthesia  of  the 
sole  of  the  foot.  In  all  wounds  of  the  leg,  systematic  inspection  should 
be  made  of  the  attitude  of  the  foot  and  the  electrical  reactions  of  the 
plantar  muscles  ;  a  simple  faradic  examination  will  generally  reveal  neg- 
lected plantar  paralysis. 

The  attitude  of  the  foot  is  rather  characteristic.  First,  it  is  a  hollow 
foot,  since  atrophy  of  the  plantar  muscles  intensifies  the  concavity  of  the 
plantar  arch,  which  is  supported  by  the  tendons  of  the  tibiales  and  the 
peroneals. 

Frequently  too  it  is  an  atrophied  foot,  owing  to  the  disappearance  of 
the  thick  mass  of  the  plantar  muscles  ;  in  some  cases,  after  a  time  we  may 
see  atrophy  of  the  foot,  which  appears  to  be  smaller,  thinner  and  shorter  than 
the  normal  foot. 

The  toes  form  a  special  kind  of  grifft  ;  the  first  phalanx  is  hyper- 
extended  on  the  metatarsus  by  the  pull  of  the  extensors  and  by  the 
inaction  of  the  flexor  interossei  of  the  first  phalanx  ;  the  second  and  third 
phalanges,  on  the  other  hand,  are  strongly  flexed  by  traction  of  the  flexor 
longus  digitorum. 

The  toes  thus  seem  to  be  bent  back  upon  themselves,   forming  a  sort 


256 


NERVE   WOUNDS 


of  Z,  the  pulp   lying  on  the  ball  of  the  toes  formed   by  the  metatarso- 
phalangeal articulations. 


Fig.  265. — Atrophy  of  the  plantar  muscles  caused 
by  lesion  of  the  posterior  tibial  at  the  lower 
part  of  the  leg. 


Fig.  266. — Pes  cavuswith 
hyper-extension  of  the 
toes  caused  by  lesion  of 
the  posterior  tibial. 


Normal  foot.  Paralysed  foot. 

Figs.  267  and  268.— Attitude  of  the  foot  in  paralysis  of  the  posterior  tibial.  On  the 
right,  left  foot  paralysed  in  characteristic  attitude.  Hyper-extension  of  the  first 
phalanx,  hyper-flexion  of  the  second  and  third  phalanges;  projection  of  the  metatarso- 
phalangeal articulations  which  constitute  the  anterior  end  of  the  arch.  On  the  left^ 
compare  the  normal  right  foot  of  the  same  patient. 

The  adduction  and  abduction  movements  of  the  toes  are  suppressed 

by  paralysis  of  the  interossei. 

The  posterior  tibial  nerve  possesses  the  same  trophic  activities  as  the 
internal  popliteal. 


sciatic  nervp: 


257 


Its  interruption  results  in  the  frequent  appearance  of  plantar  ulcers 
caused  by  injuries  from  the  boot ;  superficial  sores  which  often  take  a  very 
long  time  to  heal.  Its  irritation  brings  out  the  same  nerve  disturbances, 
particularly  fibrous  contraction  of  the  plantar  aponeurosis,  with  gr'iffe  of 
the  toes  and  muscular  sclerosis. 

Like  the  internal  popliteal,  it  may  be  the  seat  of  violent  causalgia  and 
of  prolonged  neuralgic  pains. 


III.— EXTERNAL  SAPHENOUS  NERVE 

Of  all  the  branches  of  the  internal  popliteal,  the  external  saphenous 
alone  deserves  special  mention,  for  it  may  be  affected  in  its  superficial 
course  on  the  posterior  surface  of  the  calf. 

Its  interruption  causes  anaesthesia,  limited 
to  the  external  retromalleolar  region,  to  the 
external  half  of  the  heel  and  to  the  outer 
border  of  the  foot.  It  is  followed  by  the 
usual  phenomena  of  regeneration  accom- 
panied by  unpleasant  formications  and  cuta- 
neous paresthesia  which  may  cause  pain  along 
the  course  of  the  nerve  if  anything  is  worn 
on  the  foot. 

On  the  other  hand,  irritation  of  the  nerve 
is  often  the  cause  of  painful  heel,  along  with 
cutaneous  hyper-aesthesia  so  painful  at  times 
that  the  patient  does  not  dare  to  set  his  heel 
on  the  ground  and  walks  with  difficulty, 
carrying  the  weight  of  his  body  on  the 
inner  portion  of  the  metatarso-phalangeal 
articulations. 


Fig.  269. — Sensory  area  "t 
theexternal  saphenous  nerve. 
Note  that  the  anxsthesia 
does  not  reach  the  extremity 
of  the  last  two  toes. 


IH._PARALYSIS    OF   THE    SCIATIC   TRUNK 

Lesions  of  the  great  sciatic  nerve  simply  combine  paralysis  of  the 
internal  popliteal  with  that  of  the*  external  popliteal.  Atrophy  is  complete. 
Progress,  however,  is  possible,  with  a  steppage  gait,  but  the  foot,  in  an 
absolutely  swinging  condition,  is  no  more  than  an  insensible  inert  appen- 
dage supporting  the  weight  of  the  body,  thanks  to  the  rigidity  of  the 
lower  limb,  a  rigidity  maintained  by  the  hamstring. 

In  these  cases,  there  is  considerable  and  often  widely  diffused  atrophy 
of  the  leg,  the  sensory,  trophic  and  vaso-motor  disturbances  are  more 
pronounced,  for  collateral  substitution  is  no  longer  possible. 

To  paralysis  of  the  muscles  of  leg  and  foot  may  be  added  paralysis  of 
the  posterior  muscles  of  the  thigh  supplied  by  the  collateral  branches  ot 
the  sciatic. 

17 


258 


NERVE   WOUNDS 


These  muscles  receive  their  motor  hranches  at  different  and   some- 
what variable  levels. 

The  semi-tendinosus,  supplied  wholly  at  the   upper   portion   of  the 
thi^h,  below  the  sciatic  notch,  is  scarcely  ever  injured. 

^The  semi-membranosus  and  the  long  head  of  the  biceps,  supplied  a 
little  below,  are  sometimes  paralysed. 

The  short  head  of  the  biceps,  the  motor  twig 
of  which  is  given  off  at  the  middle  of  the  thigh, 
is  very  often  affected  ;  paralysis  is  indicated  by 
appreciable  weakening  of  the  biceps. 


Fig.  270. — Lesion  of  the  sciatic  (complete 
interruption  at  the  level  of  the  sciatic 
notch).  Wound  13  months  old.  Con- 
siderable atrophy  of  all  the  muscles  of 
the  leg.  Paralysis  of  the  posterior 
muscles  of  the  legs,  except  the  semi- 
tendinosus. 


Fig.  271.- — Muscles  sup- 
plied by  the  trunk  ot 
the  sciatic  itself.  On 
the  outer  side  is  the 
biceps,  semi-tendinosus 
and  semi-membran- 
osus. 


Preservation  of  the  semi-tendinosus  suffices  in  all  these  cases  to  assure 
persistence  of  flexion  of  the  leg  on  the  thigh,  the  abolition  of  which  is 
therefore  exceptional. 

The  sciatic  nerve,  like  its  branches,  may  be  interrupted,  compressed 
or  irritated.  Injuries  of  this  nerve  may  produce  all  the  paralytic,  neuritic, 
neuralgic  and  causalgic  syndromes  which  we  have  already  studied. 

The  neuritic  types  are  extremely  frequent,  affecting  either  the  whole 
or  only  part  of  the  nerve  distribution.     They  arc  indicated   by  the  usual 


SCIATIC   NERVE 


259 


trophic  disturbances,  fibrous  infiltration  and  desquamation  of  the  skin, 
profuse  sweats  or  dryness  of  the  integuments  ;  sclerosis  of  the  dermis  ; 
muscular,  tendon,  and  aponeurotic  contractions.  They  may  immediately 
be  recognised,  simply  by  pressure  on  the  calf  or  the  sole  of  the  foot,  which 
is  extremely  painful  ;  whilst  almost  invariably  they  culminate  in  fibrous 
contraction  of  the  calf,  combined  with  pes  equinus,  and  sometimes  even 
in  fibrous  griffe  of  the  toes. 


Fig.  272. — Complete  interruption  of  the  sciatic  at  the  upper  part  of"  the  leg.  Paralysis 
of  the  biceps  and  of  the  semi-membranosus.  The  unaffected  semi-tendinosus  is 
capable  of  producing  considerable  flexion  of  the  leg  on  the  thigh.  Here  its  tendon 
shows  as  a  very  obvious  projection  on  the  inner  side  of  the  popliteal  space.  Absence 
of  contraction  of  the  biceps,  the  tendon  of  which  is  invisible  on  the  surface. 

It  must  be  remarked  that  vaso-motor  and  trophic  disturbances  of  the 
neuritic  types  are  usually  more  pronounced  in  lesions  of  the  trunk  of  the 
sciatic  than  in  wounds  of  the  internal  popliteal  or  of  the  external  popliteal, 
doubtless  because  of  the  impossibility  of  substitution. 

In  some  cases  we  find  that  simple  contusion  of  the  sciatic  nerve  gives 
rise  to  persistent  neuralgia,  veritable  traumatic  sciatica,  the  cure  of  which 
is  a  very  long  process.  The  nerve  is  painful  under  pressure  at  the  level 
of  Valleix's  points  ;  Lascgue's  sign  is  almost  always  present,  and  we  often 
note  slight  hypertonia  of  the  muscles  of  the  calf,  shown  by  a  raising  of  the 
heel,  just  as  in  common  sciatica  (Souques),  suggesting  true  pes  equinus. 

Lastly,  certain  cases  of  slight  neuritis  of  the  sciatic  produce  the  appear- 
ance of  actual  contractions  :  contraction  of  the  posterior  muscles  of  the 
leg  and  contractions  of  the  calf,  intensified  and  aggravated  as  usual  by 
disuse  on  the  part  of  the  patient  and  culminating  in  permanent  flexion 
of  the  knee  with  more  or  less  pronounced  pes  equinus. 

What  particularly  characterises  the  sciatic  is,  by  reason  of  its  bulk,  the 
frequency  of  partial  lesions  and  of  dissociated  syndromes. 

It  must  not  be  forgotten  that  bifurcation  of  the  nerve  takes  place  at 
an  extremely  variable  level,  sometimes  at  the  middle  or  even   the  upper 


260 


NERVE   WOUNDS 


part  of  the  thigh.  There  are  indeed  cases  in  which  the  two  branches  of 
the  nerve  issue  from  the  sciatic  notch  separate,  and  pass  on  together,  arranged 
in  gun-barrel  fashion. 


Fig.  273. — Severe  neuritis  of  the  sciatic  nerve.     (Edema  of  the  foot,  fibrous 
infiltration  of  the  dermis,  cyanosis,  cutaneous  desquamation. 

Even  united  in  a  single  trunk,  the  fibres  ot  the  internal  popliteal  and 
of  the  external  popliteal  retain  their  relationship,  being  grouped  together 
at  the  internal  and  external  part  of  the  nerve. 


Fig.  274.  —  Neuritis  of  the  sciatic.  Predominant  cutaneous  disturbances  scaly  skin 
peeling  off"  in  broad  flakes  (integrity  of  the  distribution  of  the  internal  saphenous). 
Trophic  disturbances  of  the  nails. 


We  may  then  observe  the  most  varied  dissociations  and  combinations 
resulting  from  lesion  of  the  sciatic.     A  few  instances  may  be  given. 

In  some  cases  we  have  complete  paralysis  of  the  internal  popliteal  or 


SCIATIC    NERVE 


261 


of  the  external  popliteal,  accompanied  by  simple  weakening  of  the  other 
nerve. 

In  other  cases,  paralysis  is  complete  in  the  nerve  distribution  of  both 
nerves,  but  whereas  it  remains  unchanging  in  the  region  of  one  of  the 
nerves,  we  find,  in  the  other,  that  a  syndrome  of  progressive  regeneration 
appears.  Even  before  the  muscles  show  the  slightest  sign  of  improvement, 
the  sign  of  formication  indicates  this  difference  in  evolution.  We  find, 
for  instance,  at  the  level  of  the  lesion,  a  definite  area  of  formication,  un- 
changing and  localised  in  the  sole  of  the  foot  ;  on  the  other  hand,  we  see 


Fig.  275. — Contraction  of  the  calf  with  pes  equinus,  caused  l>y  slight  irritation 
of  the  sciatic  at  the  upper  part  of  the  thigh. 


advancing  below  the  lesion  a  zone  of  induced  formication  which  is  localised 
on  the  dorsal  surface  of  the  foot  ;  the  conclusion  we  arrive  at  is  that  there 
exists  an  insurmountable  obstacle  to  the  fibres  of  the  internal  popliteal, 
whereas  the  fibres  of  the  external  popliteal  nerve  are  in  process  ot 
regeneration. 

We  may  find  the  association  of  simple  paralytic  disturbances  in  the 
region  of  one  of  the  nerves,  and  of  ncuritic  or  neuralgic  irritation  in 
the  region  of  the  other.  Still,  it  must  be  remembered,  in  such  cases,  that  the 
neuritic  symptoms  of  the  internal  popliteal  are  always  far  more  intense  and 


262  NERVE   WOUNDS 

obvious  ;    the  signs   of  irritation   of  the   external   popliteal,  always   more 
widely  distributed,  are  not  apparent  at  first ;  they  have  to  be  sought  for. 

The  frequency  and  diversity  of  these  dissociated  syndromes  of  the 
sciatic  are  a  matter  of  importance,  for  a  precise  diagnosis  of  the  nature  and 
seat  of  the  lesion  will  frequently  enable  us  to  carry  out  partial  and  con- 
servative interventions,  these  being  specially  easy  in  the  case  of  the 
sciatic. 


DIAGNOSIS  OF  PARALYSIS   OF  THE   SCIATIC   AND   ITS 

BRANCHES 

The  various  forms  of  paralysis  of  the  sciatic  are  easy  to  recognise. 

The  seat  of  the  wound  in  the  course  of  the  nerve,  the  topography  of 
the  paralysed  muscles,  their  atrophy  and  faradic  inexcitability  enable  us 
to  determine  the  existence  of  the  lesion  and  to  eliminate  all  the  causes  of 
error,  which  we  will  now  enumerate  : 

Hysterical  paralysis,  or  rather  the  group  of  functional  paralyses,  con- 
stitutes the  chief  difficulty  in  diagnosis. 

They  are  frequent  and  extremely  variable  as  to  their  cause.  Some- 
times we  are  dealing  with  genuine  hysterical  paralysis  or  simply  with  the 
functional  inertia  of  wounded  muscles  ;  sometimes  after  the  recovery  of  a 
nerve  lesion,  the  paralysis  persists — this  is  a  functional  condition,  the  result 
of  prolonged  disuse  of  the  muscle.  The  incapacity  results  from  the  pain, 
contracture  or  retraction  of  the  antagonistic  muscles. 

In  all  cases,  a  simple  electrical  examination  with  the  faradic  current 
will  suffice  to  show  the  functional  nature  of  the  paralysis. 

We  may  also  easily  recognise  cases  of  incapacity  caused  by  the  partial 
destruction  of  the  muscles  or  by  section  of  the  tendons ;  first,  by  the  site 
and  character  of  the  wound  ;  secondly,  and  above  all,  by  electrical  ex- 
amination. The  muscular  fibres  which  have  escaped  the  more  or  less 
complete  destruction  of  a  muscle  still  retain  some  faradic  contractility, 
unless  there  exists  an  associated  nerve  lesion.  The  divided  muscles  also 
contract,  and  the  contraction,  not  transmitted  to  the  tendon,  may  be 
regarded  as  a  definite  sign  that  they  have  been  cut. 

Lastly,  the  contractures  and  the  fibrous  cicatricial  scleroses  of  the 
muscles,  and  in  particular  the  almost  constant  contractions  of  the  calf 
resulting  from  a  wound  of  the  gastrocnemius,  or  of  the  tendo  Achillis,  or 
of  the  os  calcis,  may  easily  be  mistaken  for  neuritic  fibrous  contraction  ;  but 
the  distinctive  pain  in  cases  of  neuritis  on  pressure  on  the  nerve  trunks 
and  muscular  bellies  is  here  lacking,  and  the  muscles  have  retained  their 
faradic  contractility,  though  this  is  often  difficult  to  determine  in  retracted 
or  contracted  muscles. 


SCIATIC    NERVE 


263 


Sometimes  a  diagnosis  of  the  various  organic  paralyses  of  the  lower 
limb  is  a  little,  more  difficult. 

Frequently  peripheral  neuritis  appears  almost  identical  with  complete 
or  dissociated  paralysis  of  the  sciatic.  In  addition  to  the  typical  forms  of 
polyneuritis,  of  which  the  diphtheritic  is  the  most  frequent,  certain  forms 
of  neuritis  peculiar  to  war  must  be  mentioned  ;  of  these  we  have  found 
three  groups :  polyneuritis  resulting  from  trench  dysentery,  polyneuritis 


Fig.  276. — Complete  hysterical  paralysis  of  the  right  lower  limb,  following  a  superficial 
perforating  wound  of  the  buttock.  Slight  muscular  atrophy  from  prolonged  inaction 
(16  months),  normal  electrical  reactions,  normal  reflexes.  Complete  anaesthesia  <>t  the 
lower  limb.  The  patient,  incapable  of  using  his  right  lower  limb,  hops  along  on  his 
left  leg  with  the  help  of  a  stick,  leaving  his  right  leg  to  drag  behind  him. 

from  frost-bite,  polyneuritis  from  asphyxiating  gases,  two  instances  of 
which  we  have  localised  to  the  region  of  the  external  popliteal.  The  first 
and  third  are  generally  painless,  neuritis  from  frost-bite,  on  the  other  hand, 
is  very  painful,  being  accompanied  by  trophic  disturbances  together  with 
contraction  of  the  plantar  aponeurosis  and  of  the  plantar  muscles. 

In  all  these  cases,  the  disturbances  are  mostly  bilateral  and  symmetrical, 
though   they  may  predominate  on   one  side  ;   the  electrical   reactions  are 


264  NERVE   WOUNDS 

profoundly  affected — though,  as  a  rule,  the  tibialis  anticus  is  more  or  less 
untouched,  just  as  the  supinator  longus  is,  in  saturnine  musculo-spiral 
paralysis.  Finally,  the  absence  of  a  wound  and  the  history  of  the  case 
are  usually  sufficient  to  determine  the  diagnosis. 

Lesions  of  the  sacral  plexus  often  reproduce  the  picture  of  complete  or 
of  dissociated  paralysis  of  the  sciatic  ;  when  we  come  to  study  the  lumbo- 
sacral plexus,  we  shall  set  forth  the  special  characteristics  of  these  root 
paralyses. 

Lumbo-sacral  hematomyelia,  caused  by  lumbar  commotio  or  simply 
by  shell  explosion,  may  also  cause  errors  in  diagnosis,  but  the  root  dis- 
tribution of  the  motor  and  sensory  disturbances,  the  almost  invariable 
association  of  sphincteric  disturbances,  and,  above  all,  the  dissociation  of 
sensibility  join  with  the  history  in  clearing  up  the  diagnosis. 

We  shall  return  to  this  point  in  diagnosing  root  paralysis,  the  main 
difficulty  of  which  lies  in  cases  of  hematomyelia. 

Cortical  paralysis,  limited  to  the  lower  limb  and  following  on  wounds 
of  the  cranium,  may  in  certain  cases  be  mistaken  for  paralysis  of  the 
sciatic.  These  cortical  monoplegias,  which  are  flaccid  and  spasmodic  in 
succession,  are  characterised  by  the  absence  of  peripheral  signs,  the  integrity 
of  the  muscles  and  their  normal  electrical  reactions,  exaggeration  of  the 
reflexes,  Babinski's  sign  and  the  combined  flexion  of  thigh  and  trunk. 
We  are  far  more  likely  to  mistake  them  for  hysterical  paralysis  than  for 
paralysis  of  a  peripheral  nerve. 

Lastly,  ischaemic  paralysis  of  the  foot,  resulting  from  too  tight  a 
bandage  or  from  arterial  obliteration,  may  sometimes  be  very  difficult  to 
diagnose,  the  more  so  as  it  is  rather  frequently  associated  with  nerve 
lesions. 

As  in  paralysis  of  a  neuritic  type,  we  observe  pains  that  are  violent, 
spasmodic  and  evoked  by  pressure  ;  there  are  seen  marked  disturbances  of 
electrical  reactions  and  objective  disturbances  of  sensibility.  The  absence 
of  the  topography  characteristic  of  peripheral  nerve  lesion,  the  frequent  pre- 
servation of  an  attempt  at  contraction,  the  considerable  fall  of  temperature, 
the  cyanosis  and  fibrous  infiltration  of  the  foot,  the  suppression  of  arterial 
pulsation,  the  segmentary  distribution  of  muscular  and  sensory  disturbances 
diminishing  from  the  periphery  towards  the  root  of  the  limb  ;  all  are 
important  signs  that  enable  us  to  connect  these  paralyses  with  their  cause. 

TREATMENT   OF   PARALYSIS   OF  THE   SCIATIC 

Steppage  constitutes  the  main  functional  drawback  in  paralysis  of  the 
trunk  of  the  sciatic  or  of  the  external  popliteal.  It  is  important  to 
minimise  this,  just  as  we  minimise  the  wrist  drop  in  musculo-spiral 
paralysis,  in  order  to  diminish  the  incapacity  of  the  patient,  and  especially 
to  avoid  the  stretching  of  the  muscles  of  the  antero-external  group. 


SCIATIC    NERVE 


265 


This  is  easily  effected  either  by  surgical  boots  or  shoes,  or  by  the 
application  of  spring  contrivances;  or,  more  simply  still,  by  the  traction, 
on  the  front  part  of  the  foot,  of  a  spring  or  elastic,  fastened  either  to  a 
girdle  or  to  a  shoulder  strap. 


Types  of  apparatus 
suppressing  steppage 


Fig.  277.     (P.  Marie 
and  H.  Meige.) 


Kir..  278.     (A.  Leri. 


It  is  really  surprising  to  find  that  patients,  supplied  with  these  very 
simple  contrivances,  can  take  moderately  long  walks  without  much 
fatigue;  in  spite  of  their  paralysis  they  complain  of  only  a  very  slight 

degree  of  incapacity. 


CHAPTER    XVI 

SMALL  SCIATIC  NERVE 

The  small  sciatic  nerve  has  its  origin  in. the  first,  second,  and  third  sacral 
roots. 

It  issues  from  the  pelvis,  along  with  the  great  sciatic  nerve  and  the 


Gluteus  max 


Super,  glut 


Great  sacrosciatic 
ligament 


Long,  puden 


Small  sciatic 
N.  (per.  br.) 


-  Gluteus  mini- 
mus 

Tensor  fasciae 
femoris 


Pyramidalis 


"  Great  sciatic  N. 


Quadratus 
femoris 


Gluteus  maxi- 
mus 


Small  sciatic  N.  (glut.  br. 


Fig.  279. — Nerves  or"  the  gluteal  region.      (After  Hirschfeld,  simplified.) 

inferior  gluteal  nerve  (sacral  plexus).  Moreover,  the  inferior  gluteal  nerve 
and  the  small  sciatic  are  often  described  as  the  two  branches  of  one  and  the 
same  trunk. 

The  posterior  cutaneous  nerve  descends,  internal  to  the  great  sciatic, 
between  the  biceps  and  the  semi-tend inosus  as  far  as  the  middle  part  of 
the  popliteal  space,  where  it  divides  into  its  two  terminal  branches. 


SMALL   SCIATIC    NERVE 


267 


Collateral  Branches 

Along  its  course,  it  sends  out  a  series  of  collateral  branc 

The  gluteal  branches,  two  or  three  in  number,  which 
lower  edge  of  the  gluteus  maximus  to  be  distributed  over 
the  skin  of  the  lower  and  outer  part  of  the  buttock  ; 

The  perineal  branches  which  are  given  off  at  the 
same  level  and  are  distributed  over  the  skin  of  perineum 
and  scrotum  ; 

The  femoropopliteal  branches  which  appear  at  variable 
levels  and  are  distributed,  on  the  inner  and  the  outer 
side,  over  the  skin  of  the  posterior  part  of  the  thigh. 


Terminal  Branches 


he  : 

turn  round  the 

0   / 


1.  A  superficial  branch  which  descends  right  to  the 
middle  of  the  calf,  distributed  to  the  integuments  ; 

2.  A  deep  subaponeurotic  branch  which  proceeds 
along  the  external  saphenous  vein  and  anastomoses  with 
the  external  saphenous  nerve,  about  the  middle  part  of 
the  calf. 

The  posterior  cutaneous  nerve  of  the  thigh  is  thus 
wholly  sensory. 

Its  destruction   is    indicated    solely  by    anaesthesia  of    Fig.   280.  —  Sen 
the  posterior  surface  of  the  thigh  and  of  the  upper  part        s.ory     (lismhu 

r  d  rr        1  tion  or  tncsmal 

of  the  calf.  sciatic  nerve. 


. 


CHAPTER   XVII 


ANTERIOR  CRURAL  NERVE 


The  anterior  crural  nerve  is  formed  by  the  union  of  three  roots  springing 
from  the  second   and  particularly  the  third  and  fourth  lumbars. 

These  roots  unite  near  the  iliac  crest,  at 
the  level  of  the  outer  edge  of  the  psoas. 

The  nerve  crosses  obliquely  the  iliac 
fossa,  in  the  angle  formed  between  the  psoas 
and  the  iliacus. 

It  passes  under  Poupart's  ligament  out- 
side the  vessels  from  which  it  is  separated 
by  a  portion  of  the  psoas. 

It  is  under  Poupart's  ligament  that  it 
divides  into  its  many  terminal  branches, 
diverging  in  every  direction  across  Scarpa's 
triangle. 

The  course  of  the  nerve  trunk  then  is 
very  short ;  this  fact  explains  why  paralyses 
of  this  trunk  are  so  few. 

Collateral  Branches 

In  its  intra-pelvic  course  the  anterior 
crural  supplies  the  iliacus  and  the  psoas ;  it 
also  supplies  a  branch  to  the  femoral  artery 
and  the  nerve  to  the  pectineus. 

Fig.  281. — Anterior  crural  nerve  ami  obturator 
nerve.  (After  Sappey.)  1.  Anterior  crural 
nerve.  2,  3.  Nerve  to  the  ilio-psoas.  4.  External 
musculo-cutaneous  nerve.  5,  6,  7.  Internal  mus- 
culo-cutaneous  nerve.  8.  Branch  to  the  femoral 
artery.  9,  10,  n.  Nerve  to  the  quadriceps. 
12.  Internal  saphenous  nerve  with  13,  its  patellar 
branch  anil,  14,  its  tibial  branch.  15.  Obturator 
nerve.  16.  Branch  to  the  adductor  longus.  17.  Branch  to  the  adductor  brevis. 
18.  Branch  to  the  rectus  femoris.  19.  Branch  to  the  adductor  magnus.  20.  Lumbo- 
sacral trunk.  2i.  First  sacral  root.  22.  Abdomino-pelvic  sympathetic.  23.  External 
cutaneous  nerve. 


ANTERIOR   CRURAL   NERVE 


269 


Terminal    Branches. 

The  anterior  crural  expands  into  a  considerable  number  of  branches 
which  frequently  originate  in  two  common  trunks  and  which  we  may, 
with  Sappey,  reduce  to  four  groups. 

1.  The  external  musculo-cutancous  nerve  supplies  a  single  muscle,  the 
sartorius,  by  means  of  several  twigs  (short  and  long  branches).  It 
supplies  three  cutaneous  branches  : 


External  cutaneous  nerve 
Middle  cutaneous  nerve-f 


Mid.  cut. 
Twig  to  sartorius 


Mill,  cut, 


Access,  inter,  saph. 

Inter,  musculo-cut.  N. 
Int.  cut.  N. 
Int.  saph.  N. 


Inter,  saph.  access  N. 


Patellar  branch 


(Inter,  saphen. 
ti ranch  to  leg    J 

Fig.  282. — Cutaneous  branches  of  the  anterior  crural.     (After  Sappey.) 

The  upper  cutaneous  perforating  branch  (middle  cutaneous)  which 
passes  through  the  sartorius  and  is  distributed  over  the  antero-external 
part  of  the  thigh  internal  to  the  external  cutaneous  nerve  with  which  it 
anastomoses  ; 

The  lower  cutaneous  perforating  branch  (middle  cutaneous)  which 
descends  along  the  sartorius  and  perforates  it  at  about  its  middle  third,  to 
be  distributed  in  the  supra-patellar  region  ; 

The  accessory  branch  of  the  internal  saphenous,  one  branch  of  which 


270 


NERVE   WOUNDS 


Br.  perf, 


Inter,  saph.  vein  ■■ 


Inter,  saph.  ace. 
Inter,  saph.  N.  (patellar  br.) 


Inter,  saph.  N.  (tibial  br 


remains  close  to  the  internal  saphenous  vein,  and  the  other  the  deeper  one, 

follows  the  femoral  artery  ;  both  become  superficial  at  the  lower  and  inner 

part  of  the  thigh  and  supply  the  inner  side  of  the  knee. 

2.  The    internal    branch  whose  muscular   branches  pass    behind  the 

femoral  vessels  and  are  distributed  to  the  pectineus  and  to  the  adductor 

longus. 

The  cutaneous  branches 
which  pass  in  front  of  the 
vessels  are  distributed  over 
the  upper  and  inner  part 
of  the  thigh  and  anastomose 
with  the  cutaneous  branches 
of  the  obturator. 

3.  The  nerve  to  the 
quadriceps  from  which  origi- 
nate : 

The  branch  to  the  rectus 
femoris  ; 

The  branch  to  the  vastus 
externus  ; 

The  branch  to  the  vastus 
internus ; 

The  branch  to  the  crureus. 

4.  The  internal  saphe- 
nous nerve  rejoins  the  femoral 
artery  and  descends  into  the 
sheath  of  the  femoral  vessels 
in  front  of  the  artery  which 
it  crosses  obliquely  so  as  to 
lie  internal  to  it. 

At  the  lower  part  of  the 
thigh,  near  the  opening  in 
the  adductor  magnus,  it  leaves 
the  vessels,  perforates  the 
anterior  wall  of  Hunter's 
canal  and  proceeds  along  the 
inner  side  of  the  knee. 

Becoming  subcutaneous 
at  the  level  of  the  internal  tuberosity  of  the  tibia,  it  lies  along  the  internal 
saphenous  vein  which  its  main  terminal  (tibial)  branch  accompanies  right 
to  the  inner  side  of  the  foot. 

Its  collateral  branches,  of  but  slight  importance,  are : 

The  femoral  cutaneous  branch  ; 

The  tibial  cutaneous  branch  ; 

The  internal  articular  branch  to  the  knee. 


Inter,  saph.  vein  — 


Post.  tib.  N.  (calc.  br.)... 

Musculo-cutaneous  N. 

Inter,  saph.  N. 
Inter,  saph.  V. 


Fig.  283. — Internal  saphenous  nerve. 
(After  Hirschfeld.) 


ANTERIOR    CRURAL   NERVE 


271 


It  has  two  terminal  branches  : 

The  patellar  or  anterior  branch,  which  breaks  away  at  the  inner  side  of 
the  knee  and  supplies  the  supero-internal  part  of  the  leg. 

The  tibial  or  lower  branch,  which  proceeds  along  the  internal  saphenous 
vein  and  accompanies  it  throughout  its  entire  course,  supplying  branches 
to  the  whole  inner  surface  of  the  leg. 

Its  posterior  branch  is  distributed  over  the  internal  malleolar  region. 

Its  anterior  branch  passes  in  front  of  the  malleolus  and  is  distributed  on 
the  inner  side  of  the  foot  as  far  as  the  base  of  the  first  metatarsal. 


PARALYSIS  OF  THE  ANTERIOR  CRURAL  NERVE 

Paralysis  of  the  anterior  crural  nerve  is  comparatively  rare.     This  nerve 
has    quite    a    short    course    which    corresponds    solely 
to  the   point    at    which    it    crosses    the    pelvis,  where  ff 

it  is  protected  by  the  pelvic  girdle.  Immediately 
under  Poupart's  ligament  it  opens  out  into  its 
terminal  branches  and  if  the  nerve  is  injured,  in 
Scarpa's  triangle,  only  some  of  its  terminal  branches 
are  affected. 

Paralysis  of  this  nerve,  therefore,  is  generally  the 
result  of  pelvic  injuries. 

Injury  to  the  anterior  crural  nerve  is  shown  solely 
by  paralysis  of  the  pectineus,  of  the  sartorius  and  of 
the  quadriceps,  accompanied  by  loss  of  extension  of 
the  leg  on  the  thigh. 

Atrophy  of  the  crureus,  absence  of  its  power  of 
extension,  loss  of  its  normal  electrical  reactions  and 
abolition  of  the  patellar  reflex  are  so  many  signs 
that  enable  us  to  recognise  paralysis  of  this  nerve. 

As  a  rule,  the  patient  can  walk,  but  he  does  so 
with  his  leg  stiffened  by  contraction  of  the  tensor 
fasciae  femoris,  and  the  gracilis,  for  the  lower  limb, 
thus  maintained  in  a  kind  of  hyper-extension,  easily 
bears  the  weight  of  the  body  ;  but  if  the  slightest 
flexion  takes  place,  the  crureus  muscle  ceases  to  func- 
tion and  the  patient  sinks  down  on  to  his  suddenly 
flexed  knee.  He  has  also  a  special  way  of  walk- 
ing; advancing  the  healthy  limb,  he  brings  up  the 
paralysed  one,  plants  it  on  the  ground  in  hyper- 
extension,  maintained  by  contraction  of  the  tensor 
fasciae  femoris  and  of  the  gracilis,  and,  on  this  un-  |.|(.  ,s  —Musclea 
stable  support,   again    begins  to  advance  the   healthy      supplied  by  tin-  an 

Jjmk  tenor    crural  :     sar- 

*  tonus,       pectineus, 

As  in  fracture  of  the  patella,  walking  backwards  is      quadriceps. 


272 


NERVE    WOUNDS 


as  easy  as  walking  forwards  is  difficult,  for  in  this  case  the   knee  remains 
in  a  state  of  permanent  hyper-extension. 

A  frequent  cause  of  error  must  be  mentioned  in  summing  up  anterior 
crural  paralysis.  We  sometimes  imagine  that  voluntary  muscular  con- 
tractions persist  just  as  we  may  observe  electrical  pseudo-contractions 
of  the  paralysed  crural  triceps.  This  error  originates  in  the  voluntary  or 
electrical  contraction  of  the  tensor  fasciae  femoris  (superior  gluteal  nerve), 


Figs.  285  and  286. —  Paralysis  of  the  right  anterior  crural  nerve  by  intra-pelvic  lesion, 
above  Poupart's  ligament  ;  slight  consecutive  hydrarthrosis  of  the  right  knee. 

which  thrusts  inwards  the  triceps  and  imparts  to  it  a  transverse  pull  by 
means  of  its  aponeurotic  slip. 

It  must  not  be  forgotten  that  paralysis  of  the  anterior  crural  is  often 
accompanied  by  hydrarthrosis  of  the  knee,  probably  caused  partly  by  the 
slight  and  oft-repeated  injuries  which  this  articulation  now  has  to  sustain 
and  partly  by  the  hyper-extension  necessary  for  walking. 

Disturbances  of  sensibility  are  localised  on  the  anterior  surface  of  the 
thigh  and  on  the  inner  surface  of  the  leg. 

A  special  study  must  be  made  of  these  latter  disturbances  and  of 
lesions  of  the  internal  saphenous. 


LESIONS  OF  THE  INTERNAL  SAPHENOUS  NERVE. 

Of  all  the  branches  of  the  anterior  crural  nerve,  the  internal  saphenous 
is  the  only  one  the  lesion  of  which  is  of  special  interest,  since  lesion  of 


ANTERIOR   CRURAL   NERVE 


273 


the  other  terminal  branches  causes  no  more  than  partial  paralysis  of  the 
sartorius  and  the  crural  triceps. 

The  long  course  of  the  internal  saphenous  exposes  it  to  frequent  lesions 
capable  of  producing  the  various  syndromes  of  simple  anaesthesia,  neuralgia 
from  nerve  irritation,  or  even  actual  causalgia. 

Its  distribution  covers  the  entire  inner  surface  of  the  leg  and  spreads 
upwards  on  to  the  antero-internal  surface  of  the  knee.     It  extends  over 


III 


4 


1  li 


Anterior  surface.  Posterior  surface.  Inner  surface. 

Fig.  287.  Fig.  288.  Fig.  289. 

Figs.  287  and  288. — Sensory  region  of  the  anterior  crural.     Above  the  knee,  region 

of  the  anterior  crural  proper.     Below  the  knee,  region  of  the  internal  saphenous. 

Fig.  2S9. — Sensory  disturbances  in  complete  interruption  ot   the  internal  saphenous 

nerve  in  Scarpa's  triangle. 

the  internal  malleolar  region  and  over  the  inner  side  of  the  foot,  to 
end  near  the  first  metatarsal. 

It  is  often  somewhat  enlarged  in  its  upper  part  by  simultaneous  lesion 
of  the  branch  accessory  to  the  internal  saphenous,  which  follows  in  the 
thigh  the  same  course  as  the  internal  saphenous  and  is  also  affected  as 
a  rule. 

Neuralgia  of  the  internal  saphenous  is  at  times  so  violent  as  to  cause 
considerable  inconvenience  in  walking. 


DIAGNOSIS 


The  diagnosis  of  paralysis  of  the  anterior  crural  must  be  made  from 
functional   paralysis  and   from  reflex  muscular  atrophies  which  generally 

18 


274  NERVE   WOUNDS 

follow    fractures    of    the    femur    and    particularly    lesions    of    the    knee 
joint. 

Particular  care  must  be  taken  in  dealing  with  lesions  of  the  lumbar 
roots  or  with  lumbar  hematomyelias,  which  we  will  study  along  with  the 
syndromes  of  the  lumbo-sacral  plexus. 


CHAPTER   XVIII 


OBTURATOR   NERVE 

The   obturator   nerve  originates  in  the  lumbar  plexus  from  the  second, 

third,  and  fourth  lumbar  roots. 

It  appears  internal  to  the  psoas,  passes 
behind  the  common  iliac  vessels  and  pro- 
ceeds along  the  brim  of  the  inlet  right 
to  the  subpubic  groove,  covered  by  the 
parietal  peritoneum. 


Superficial  layer. 


Deep  layer. 
Fig.  292. 


Fig.  290.  Fig.  291. 

Fig.  290.— Anterior  crural  nerve  and  obturator  nerve.  (After  Sappey.)  1.  Anterior 
crural  nerve.  2,  3.  Nerve  to  the  ilio-psoas.  4.  External  branch  of  anterior  crural 
nerve.  5,  6,  7.  Internal  branch  of  anterior  crural.  8.  Branch  to  tin-  femoral  artery. 
9,  10,  ti.  Nerve  to  the  quadriceps.  12.  Internal  saphenous  nerve,  with  .3-  its 
patellar  branch  and  i+,  its  tibial  branch.  15.  Obturator  nerve.  16.  Branch  .0  the 
adductor  longus.  17.  Branch  to  the  adductor  brevis.  18.  Branch  to  the  gracilis. 
19.  Branch  to  the  adductor  raagnuB.  20.  Lumbo-sacral  cord.  zi.  1'  irst  sacral  toot. 
22.  Abdomino.pelvic  sympathetic.     23.    External  cutaneous  nerve. 

FlGS.  29!  and  292.— Muscles  supplied  by  the  obturator  nerve.    Superficial   aver  1  ;.,Muc  o, 
longus,  adductor  magnus,  gracilis.    Deep  layer  ,  the  sartonus,  t he  crural  triceps  and  the 
pectineus  (crural  nerve)  hav,  been  removed,  and  the  adductor  longus  (obturator  nerve 
has  been  cut  to  show  the  obturator  externusand  the  adductor  brevis,  as  well  as  the 
lower  part  of  the  adductor  magnus  and  of  the  gracilis. 


276 


NERVE   WOUNDS 


On  leaving  the  obturator  foramen  or  even  in  the  subpubic  groove  it 
divides  into  its  terminal  branches. 


Branches 

In  its  pelvic  course  it  supplies  chiefly  the  branch  to  the  obturator 
internus. 

There  are  two  terminal  branches — 
1.  Superficial  branch,  which   passes 
in  front  of  the  adductor  brevis  and  then 
winds  below  the  adductor  longus. 
It  supplies  at  this  level  : 
The  branch  to  the  gracilis  ; 
The  branch  to  the  adductor  brevis  ; 
The  branch  to  the  adductor  longus  ; 
A  cutaneous  branch  which  is  distri- 
buted   over  the   supero-internal    surface 
of  the  thigh  and  anastomoses  with  the 
internal  saphenous. 

2.  Deep  branch. — This,  on  the  other 
hand,  passes  behind  the  adductor  brevis 
and  supplies  the  adductor  magnus  on 
which  it  rests. 

The  obturator  nerve  is  essentially 
the  nerve  of  adduction  of  the  thigh.  Its 
secondary  function  is  to  rotate  outwards 
and  to  flex  the  thigh  on  the  pelvis. 

As  a  rule,  adduction  is  not  com- 
pletely paralysed  in  lesions  of  the 
obturator  nerve,  for  the  adductor  longus  receives  secondarv  innervation 
from  the  anterior  crural ;  the  adductor  magnus  also  receives  some  twigs 
from  the  sciatic. 

Sensory  disturbances  appear  in  a  triangular  area  occupying  the  inner 
surface  of  the  thigh. 

Lesions  of  the  obturator  are  even  more  rare  than  those  of  the  anterior 
crural ;  like  the  latter  it  has  a  somewhat  short  trunk,  also  very  effective 
protection  is  afforded  it  by  the  bones  and  muscles  of  the  pelvic  girdle. 


Figs.  293  and  294. — Sensory  region 
of  the  obturator. 


CHAPTER   XIX 
EXTERNAL  CUTANEOUS  NERVE  OF  THIGH 

The  external  cutaneous  nerve  originates  in  the  second  and  third  lumbar 
roots. 


branch.  15.  Its'gcnital  branch.  16,  17,  17'.  The  trunk,  gluteal  ami  femoral  branches 
of  the  external  cutaneous.  18.  Genital  branch,  and  19,  19',  crural  branch  <>t  the 
genito-crural.     20,  20'.  Anterior  crural  nerve.     21,21'.     Obturator  nerve. 

It  emerges  from  the  outer  edge  of  the  psoas,  crosses  the  iliac  crest,  and 


278 


NERVE   WOUNDS 


IV 


goes  on   its  way  lying  on  the  inner  surface  of  the  pelvis  a  little  below  the 

iliac  crest,  pressed  against  the  iliacus  by  the  parietal  layer  of  the  peritoneum. 

,  It  issues  from  the  pelvis  through  the 

Lj'  /      i  notch  between  the  antero-superior  iliac 

spine  and  the  antero-inferior  iliac  spine. 
It  then  divides  into  a  posterior  or 
gluteal  branch  which  is  destined  for  the 
integuments  of  the  supero-external  part 
of  the  buttock  and  into  two  femoral 
branches  distributed  over  the  skin  of  the 
outer  part  of  the  thigh. 

Anaesthesia  of  this  nerve  covers  a 
region  corresponding  to  the  outer  part 
of  the  thigh  ;  its  irritation,  which  is 
rather  frequent,  causes  the  appearance 
of  a  somewhat  special  neuralgia  covering 
the  entire  outer  surface  of  the  thigh, 
rendering  painful  the  contraction  of  the 
extensor  fasciae  femoris,  and  known  ever 
since  the  description  given  of  it  by 
W.  Roth  (1895)  under  the  name  of 
neuralgia  paraesthetica. 

Several  cases  have  been  mentioned  of 
lesion  of  the  external-cutaneous  accom- 
panied by  painful  irritation  of  the  causalgic  type. 


Figs.  296  and  297. — Sensory  region 
oi  the  external  cutaneous. 


CHAPTER   XX 


GENITO-CRURAL   NERVE 


\ 


U 


The  genito-crural  nerve  originates  almost  exclusively  in  the  second 
lumbar  root. 

It  makes  its  way  forwards  across  the  fibres  of  the   psoas,  emerges  on 
the   anterior  surface  of  this  muscle,  and    descends,  , 

parallel  to  this  latter,  right  to  the  antero-inferior 
iliac  spine,  below  which  it  passes  under  Poupart's 
ligament.     It  divides  into  two  terminal  branches  : 

1.  The  external  or  crural  branch  passes  under 
Poupart's  ligament  outside  of  the  iliac  vessels  to 
which  it  is  applied,  separated  consequently  from  the 
anterior  crural  nerve  by  the  tendon  of  the  psoas. 

It  perforates  the  fascia  in  front  of  the  vessels 
and  becomes  superficial,  afterwards  it  spreads  over 
the  integuments  of  the  antero-internal  surface  of 
the  thigh. 

There  it  supplies  a  small  sensory  region,  oval 
in  form,  covering  almost  the  whole  of  Scarpa's 
triangle. 

2.  The  internal  or  genital  branch  breaks  away 
from  the  former  before  passing  under  Poupart's 
ligament  ;  it  bends  back  inwards  to  reach  the 
inguinal  canal  through  which  it  passes  together  with 
the  vas  deferens. 

It  penetrates  into  the  scrotum  and  is  distributed 
over  the  skin  of  the  scrotum  and  to  the  contiguous 
area  of  the  inner  surface  of  the  thigh. 

Lesions    of   the    genito-crural    nerve    are    very    v 

&  }     riG.298. — Sensory  region 

rare;  they  show  themselves,  for  the  most  part,   in        of  the  genito-crural. 
sensory  disturbances.     We  have  met  with  lesions 

that  irritate  the  nerve,  in  the  course  of  wounds  of  the  abdominal  wall, 
manifesting  themselves  by  painful  hyper-aesthesia  at  the  root  of  the  thigh 
and  in  the  scrotum. 


CHAPTER  XXI 


ILIO-HYPOGASTRIC  NERVE 


u    /^ 


V 


The  ilio-hypogastric  continues  the  first  lumbar  root  and  makes  its  way 
obliquely  towards  the  iliac  crest,  passing  along  its  upper  border,  lying 
between  the  internal  oblique  and  the  transversalis  abdominis. 

i.  It  gives  off  along  its  course  a  perforating   branch  which  appears 

above  the  gluteus  maximus  and  supplies 
the  outer  and  upper  part  of  the 
buttock. 

2.  It  supplies  a  musculo-cutaneous 
branch  or  abdominal  branch  which  gives 
some  motor  twigs  to  the  internal  oblique 
and  to  the  transversalis,  and  is  distri- 
buted, by  way  of  a  perforating  branch, 
over  the  skin  of  the  lower  part  of  the 
abdomen. 

3.  The  third — genital — branch  pro- 
ceeds along  the  upper  surface  of  Poupart's 
ligament,  lying  in  the  depth  of  the 
abdominal  wall,  between  the  transversalis 
and  the  internal  oblique. 

It  thus  enters  the  inguinal  canal  and 
emerges  to  spread  out  at  the  external 
inguinal  ring  into  branches  which  are  distributed  over  the  supero-internal 
part  of  the  thigh. 


Figs.  299  and  300. — Sensory  region 
of  the  ilio-hypogastric. 


ILIOINGUINAL 

The  ilio-inguinal  appears  as  a  collateral  trunk  of  the  ilio-hypogastric. 

It  originates  in  the  first  lumbar,  proceeds  like  the  latter  along  its  lower 
border,  supplies  a  few  muscular  branches  to  the  internal  oblique  and  the 
transversalis,  and  joins  the  ilio-hypogastric  before  leaving  the  inguinal 
canal. 


The  ilio-hypogastric    and   ilio-inguinal  *   together  really  act  as  a  true 
intercostal    nerve  :  their    oblique  course  in   the    depth  of  the  abdominal 

*  The  description  of  these  two  nerves  differs  in  some  particulars  from  that  current  in  English 
Text-books. — (Ed.) 


ILIOHYPOGASTRIC    NERVE  281 

wall,  the  motor  branches  supplied  to  the  muscles  of  the  abdomen,  the  two 
lateral  perforating  cutaneous  branches,  and  their  terminal  branch  issuing 
from  the  inguinal  canal,  represent  the  three  perforating  brandies  of  the 
intercostal  nerves. 

Their  sensory  region  consists,  as  does  that  of  the  intercostals,  of  an 
oblique  tract  which  passes  along  the  margin  of  the  pelvic  girdle  but  spreads 
over  the  root  of  the  lower  limb  at  the  points  where  the  three  perforating 
branches  emerge.  The  result  of  this  is  a  sinuous  tract  corresponding  to 
the  similar  sinuosities  of  the  twelfth  intercostal  nerve. 


CHAPTER   XXII 
LUMBO-SACRAL   PLEXUS 

From  the  lumbo-sacral  plexus  all  the  nerves  of  the  lower  limb  originate. 
It  consists  of  two  distinct  parts:  the  lumbar  plexus,  formed  by  the  first 
four  roots  ;  the  sacral  plexus,  consisting  of  the  fifth  lumbar  root,  and  the 
first,  second  and  third  sacral. 

XII  D 


I  L 


Iliohypogastric  and  ilio-inguina 


External  cutaneous 


Anterior  crural 


IV  L 


VL 


Obturator 

Lumbo-sacral  cord 
Fig.  301. — Lumbar  plexus. 

All  the  roots  of  these  plexuses  are  united  to  one  another  by  vertical 
anastomoses,  which  form  actual  nerve  loops  from  which  the  trunks  that 
constitute  the  peripheral  nerves  are  given  off. 


LUMBOSACRAL   PLEXUS 


2«3 


LUMBAR   PLEXUS 

A  very  simple  description  of  the  common  types  of  lumbar  plexus  may 
be  given. 

The  first  lumbar  root  gives  off  the  ilio-hypogastric  ami  the  ilio-inguinal 
with  the  aid  of  the  anastomotic  loop  originating  in  the  twelfth  dorsal. 

The  second  lumbar  root  supplies  the  external  cutaneous  and  thegenito- 
crural,  with  the  aid  of  the  anastomotic  loop  originating  in  the  first  lumbar. 


Ganglions  of  the 
sympathetic 


Fig.  302. — Connections  between  the  lumbar  plexus  and  its  branches, 

The  anterior  crural  nerve  is  for  the  most  part  formed  of  the  fibres 
originating  in  the  third  lumbar,  but  it  also  receives  an  important  contri- 
bution from  the  second  lumbar  and  even  a  more  important  one  from  the 
fourth  lumbar. 

It  is  the  fourth  lumbar  that  supplies  the  obturator  which  also  receives 
fibres  from  the  third  and  even  from  the  second  lumbar. 


284 


NERVE   WOUNDS 


From  the  fourth  lumbar  there  also  breaks  away  an  anastomotic  loop 
which  unites  with  the  fifth  lumbar  to  constitute  the  lumbo-sacral  trunk, 
the  upper  root  of  the  sacral  plexus. 

The  lumbar  plexus  is  covered,  on  the  sides  of  the  vertebral  column, 
by  the  belly  of  the  psoas  muscle. 

Through  the  fasciculi  of  this  muscle  emerge  the  different  nerves  formed 
by    the    plexus ;    the    ilio-hypogastric    and    ilio-inguinal    above    and     the 


Ext.  cutan.  nerve — -Jp?. 


Genito-crural  N 


5th  lumbar  ganglion 


Obturator  N. 


Sup.  glut.  N. 


N.  to  obtur.  int.  -! 


Lumbo-sacral 
cord 

1  st  sacral  N. 


2nd  sacral  N. 
N.  to  levator  ani 
Pudic  nerve 
Inf.  hemorr.  N. 
N.  dors,  penis 
Sup.  perineal  N. 


Dorsal  N.  penis 
N.  to  trans,  perinei 


Long  pudendal  N. 
Small  sciatic  N. 


Fig.  303. — Sacral  plexus.     (After  Hirschfeld.)     Collateral  branches. 

anterior  crural  below  appear  on  its  external  border,  the  external-cutaneous 
on  its  anterior  surface,  the  genito-crural  and  the  obturator  on  its  internal 
border. 

The  collateral  branches  of  the  plexus  are  of  slight  importance  ;  they 
are  the  branches  supplied  to  the  quadratus  lumborum  and  to  the  psoas  by 
the  first  two  lumbar  roots. 


SACRAL   PLEXUS 


The  sacral  plexus  consists  essentially  of  the  fusion  of  the  lumbo-sacral 
cord  (fifth  lumbar  and  an  anastomotic   branch  of  the  fourth  lumbar)  and 


LUMBO-SACRAL    PLEXUS 


285 


of  the  first  three  sacral  roots,  in  one  bulky  trunk  :  the  great  sciatic 
nerve. 

It  supplies  several  important  collateral  branches  : 

I.  The  superior  gluteal  nerve,  which  originates  in  the  lumbo-sacral 
cord  and  the  first  sacral,  issues  through  the  great  sciatic  notch,  passes  above 
the  pyramidalis,  and  proceeds  between  the  gluteus  minimus  and  the 
gluteus  medius,  divides  into  an  ascending  branch  and  a  descending  branch 
which  penetrates  into  the  tensor  fascia  femoris.  It  supplies  the  gluteus 
minimus,  the  gluteus  medius  and  the  tensor  fascia?  femoris  ; 


Obturator 


Superior  gluteal 

Pyramidalis 

Superior  gemellus 

Inferior  gemellus 
Quatlratus  femoris 


Small  sciatic  N. 


Lumbo-sacral  cordr  — 


*  /4('A    '••   Levator       &*"** 
/!•'!''',   \\     ani  '*;-- Sacro-coccygeal  ple> 

;,' V|\obt.  inter.  ««^_. 

\\     - >  Int.  Hemor. </-'/,;' 


« »    *  Inf.  Hemor.  tfff& 

,** 
/ 

Piulic  N. 


Great  Sciatic  N. 


Fig.  304. — Sacral  plexus. 


2.  The  nerve  to  the  obturator  internus,  which  also  originates  in  the 
lumbo-sacral  cord  and  the  first  sacral,  proceeds  forwards  into  the  inferior 
pelvi-rectal  space  and  supplies  the  obturator  internus  muscle  ; 

3.  The  nerves  to  the  pelvi-trochanteric  muscles  which  are  given  oft 
from  the  first,  second  and  third  sacrals,  and  are  distributed  to  the  pyramidalis, 
the  quadratus  femoris,  and  the  gemellus  superior  and  gemellus  inferior 
muscles  ; 

4.  The  inferior  gluteal  nerve,  which  originates  in  the  fifth  lumbar  ami 
the  first  and  second  sacral,  accompanies  the  great  sciatic  nerve  and  appears 
with  it  below  the  pyramidalis,  to  split  up  on  the  deep  surface  of  the  gluteus 
maximus  which  it  supplies  by  means  of  a  series  of  ascending  and  descending 
branches. 

It   is  to  the  somewhat   frequent   union   of  this  nerve   trunk   with   the 


286 


NERVE   WOUNDS 


posterior  cutaneous  nerve  of  the  thigh  that  we  sometimes  give  the  name 
of  small  sciatic,  regarded  in  this  case  as  a  terminal  branch  of  the  lumbo- 
sacral plexus. 

As  a  matter  of  fact,  however,  the  great  sciatic  alone  includes  in  itself 
all  the  branches  of  the  plexus  of  which  it  is  the  sole  terminal  trunk.     It  is, 


Gluteus  max 


-Gluteus  minimus 

-Tensor  fasciae 
femoris 


Pyramidalis 


Post,  cutan. 

N.  (peron. 

br.) 


Great  sciatic 

nerve 
Quadratus 

femoris 


-Gluteus  maxi- 
mus 


Post,  cutan 


Fig.  305. — Nerves  of  the  gluteal  region.     (After  Hirscbfelcl,  simplified.) 


according  to  Cruveilhier's  expression,  "  the  sacral  plexus  condensed  in  one 
nerve  trunk." 

The  collateral  branches  of  the  sacral  plexus,  along  with  the  great 
original  trunks  of  the  sciatic,  constitute  quite  an  inextricable  network 
of  nerves  which  covers  the  entire  posterior  surface  of  the  pelvic  cavity. 

PUDENDAL   PLEXUS 

The  anastomotic  loop,  which  unites  the  third  to  the  fourth  sacral, 
forms  with  this  latter  root  and  the  loop  of  the  fifth  sacral  the  origins  of 
the  pudendal  plexus. 

This  plexus  supplies  several  collateral  branches  and  a  terminal  branch  : 
the  pudic  nerve. 

The  collateral  branches  are  distributed  : 

To  the  levator  ani  and  the  ischiococcygeus  ; 


LUMBO-SACRAL   PLEXUS 


287 


To    the   sphincter    ani    and    the    skin    of   the    anal   margin    (inferior 
hemorrhoidal  or  anal  nerve). 

The  pudic  nerve,  terminal  branch  of  the  plexus,  issues  from  the  pelvic 
cavity   below   the   pyrami- 
dalis,  internal  to  the  sciatic ; 

it  crosses  the   ischio-rectal  s^^llWi-    I   (\ 

fossa    in     the    aponeurotic  //  \}j] :    \   Vi 

sheath  of  the  obturator  in- 

ternus  ;  at  the  level  of  the  ^^     (  (\\lfi     \  \j 

tuberosity  of  the  ischium 
it  divides  into  its  two 
terminal  branches,  the 
perineal  nerve  and  the 
dorsal  nerve  of  the  penis. 


RADICULAR  SYN 

DROMES      OF     THE 

LUMBOSACRAL 
PLEXUS 


Ilio-hypogastric  and 
ilioinguinal 


Ext.  cutaneous  and 
genito-crural 


Anterior  crural 


Obturator 


1 


The  roots  of  the  lumbo- 
sacral plexus  are  not  only 
affected  by  traumatisms  of 
the  pelvic  cavity,  they  may 
also,  and  perhaps  more  fre- 
quently, be  found  injured 
in  their  long  intra-spinal 
course.  Indeed,  they  form, 
in  the  whole  of  the  spinal 
canal  which  stretches  be- 
low the  first  lumbar  ver- 
tebra, a  compact  bundle, 
cauda  equina,  from  which 
they  break  away  one  after 
the  other  to  reach  the 
inter-vertebral  foramina. 
Along  this  course,  they  are 
successively  intra-dural  and  FlG-  3o6.-Intra.spinal  course  of  the  luml,,,,,,  ,.,i 
3  roots ;    cauda  equina,       I  lie    tlural     cul-de-sac    is 

extra-dural.     We  must  re-        dotted. 

member  that  the  cul-de-sac 

of  dura  mater  ends  in  the  vicinity  of  the  second  sacral  vertebra. 

Fractures  of  the  spine,  depressed  fracture  of  the  sacrum,  bullets  or  shell 
splinters  penetrating  into  the  spinal  canal,  always  affect  several  roots  at 
once,  producing  the  different  syndromes  of  the  cauda  equina. 

There  is  no  occasion   to  consider  here,  as  in  the  case  of  the   brachial 


Sciatic 


XI  D 


XII 


I  L 


D" 


HI 


IV 


288  NERVE   WOUNDS 

plexus,  root  and  trunk  syndromes.  It  is  sufficient  to  compare  the  principal 
root  syndromes  of  the  lumbo-sacral  plexus  with  the  syndromes  of  the 
peripheral  nerves. 

Whether  intra-spinal    or    extra-spinal,    lesions   of  the   roots    may    be 
recognised  by  their  special  root  topography. 


Periphera 

areas. 

Anterior  view 


Root  areas. 


Peripheral 

areas. 

Posterior  view. 


Figs.  307  and  308. — Lumbo-sacral  plexus.     Sensory  topography.     Peripheral  and 

radicular  areas. 


The  peripheral  nerves  always  contain  fibres  coming  from  several 
roots  ;  consequently,  the  root  lesions  will  for  the  most  part  give  rise  to 
dissociated  peripheral  paralyses.  On  the  other  hand,  almost  all  the  nerves 
receive  their  supply  from  several  roots,  consequently  no  complete 
paralysis  will  be  observed  unless  several  roots  are  injured  at  the  same 
time. 

Disturbances  of  sensation,   likewise,  are  characterised    by  a  different 


LUMBOSACRAL   PLEXUS 


289 


topography  from  the  peripheral  distribution  ;  they  appear  in  the  form  of 
longitudinal  tracts  almost  parallel  to  the  axis  of  the  limb  in  the  case  of  the 
sacral  and  lower  lumbar  roots,  arranged  obliquely  in  the  case  of  the  upper 
lumbar  roots  which  constitute  a  sort  of  transition  from  the  almost  horizontal 
topography  of  the  dorsal  roots. 

Lastly,  the  motor  and  sensory  roots  may  be  injured  independently  of 
one  another  in  the  spinal  canal  ;  we  then  find  dissociation  between  the 
motor  and  the  sensory  areas. 


LUMBAR   ROOTS 

The  upper  roots  of  the  lumbar  plexus  (first  and  second)  have  only  a 
very  secondary  motor  role  ;  they  supply  a  few  fibres  to  the  psoas,  to  the 

quadratus  lumborum,  to  the  lower  part  of  the 
transversalis  abdominis  and  to  the  anterior 
muscles   of  the  thigh.     Injury  does   not  cause 


Fig 


309. — Root  topography 
in  lesion  of  the  first  and 
second  lumbar  roots. 


Fig.  310. — Associated  paralysis  of  the 
anterior  crural  and  of  the  obturator, 
caused  by  injury  of  the  third  and 
fourth  lumbar  roots. 


paralysis,  but  simply  an  enfeebled  condition  of  these  muscles. 

Their  sensory  region  comprises  the  outer  surface  of  the  buttock  and  of 
the  root  of  the  thigh  ;  it  spreads  over  the  anterior  surface  of  the  thigh  and 
passes  slightly  beyond,  on  to  the  upper  part  of  the  outer  surface. 

The  lower  roots  of  the  lumbar  plexus  (third  and  fourth  lumbar  and 
fibres  from  the  fifth  lumbar),  on  the  other  hand,  occupy  a  very  important 
motor  region.  It  comprises  all  the  anterior  and  internal  muscles  of  the 
thigh  ;    the  crural   triceps,  the    pectineus  and   the  sartorius,  through   the 

*9 


290 


NERVE   WOUNDS 


anterior  crural  nerve  ;  the  adductors  and  the  gracilis  through  the  obturator 
nerve. 

Injury  to  these  roots  affects  both  the  area  of  the  anterior  crural  and 
that  of  the  obturator,  giving  the  atrophied  thigh  a  special  appearance,  as 
though  it  were  strangled  in  its  middle  part. 

Finally,  the  fourth  and  fifth  lumbar  roots 
supply  a  certain  number  of  fibres  to  the  glutei, 
to  the  tensor  fasciae  femoris,  to  the  posterior 
muscles  of  the  thigh  and  to  the  muscles  of 
the  leg,  which  may  consequently  be  slightly 
weakened. 

Among  the  muscles  in  which  atrophy  and 
weakness  consequent  on  lesions  of  the  fourth 
and    fifth    lumbar    roots 
/    i,"°~  are  manifested,  we  must 

j\J"  specially  note  the  tibialis 

anticus  ;  the  extensor 
communis  digitorum  and 
the  extensor  proprius  hal- 
lucis,  as  well  as  the  inner 
head  of  gastrocnemius, 
also  receive  lumbar  fibres, 
though  fewer  in  number. 
Though  dependent  on 
the  external  popliteal,  the 
tibialis  anticus  is  almost 
entirely  supplied  by  the 
fourth  and  fifth  lumbar 
roots  ;  atrophy  and  para- 
lysis in  lesions  of  the 
lower  part  of  the  lumbar 
plexus  are  almost  com- 
plete ;  its  preservation 
also  in  lesions  of  the  first 
and  second  sacral  roots 
contrasts  strikingly  with 
the  complete  paralysis  of 
the  peronei.  It  acts  as  the 
supinator  longus  muscle 
—  of  which  it  is  really 
Like  this  muscle  also  it  belongs 


Fig. 


3ii- 


Fig. 


312. 


Fig.  311. — Muscles  supplied  by  the  third,  fourth  and 
fifth  lumbar  loots.  Note  that  the  tibialis  anticus  is 
supplied  almost  solely  by  lumbar  fibres.  The  ex- 
tensors and  the  inner  head  of  gastrocnemius  receive 
only  a  few  fibres. 

Fig.  312. — Sensory  area  of"  the  third,  fourth  and  fifth 
lumbar  roots. 


the  homologue — does  in  the  upper  limb. 
to  the  upper  root  group  of  the  limb. 

The  sensory  area  of  the  last  lumbar  roots  spreads  obliquely  over  the 
outer  surface  of  the  thigh,  the  anterior  and  inner  surface  of  the  knee, 
and  the  whole  inner  surface  of  leg  and  foot.     The  patellar  reflex,  which 


LUMBO-SACRAL   PLEXUS 


291 


corresponds  essentially  to  the  third  and  fourtli  lumbar  roots,  is  always 
abolished,  both  by  anaesthesia  of  the  point  of  origin  of  the  reflex  and  by 
suppression  of  the  motor  response. 

SACRAL  ROOTS 

The  fibres  of  the  first  two  sacral  roots  are  distributed  over  the  region  of 
the  great  sciatic  nerve,  with  the  exception  of  the  tibialis  anticus  which  is 
exclusively  supplied  by  L4  and  L5  ; 
the  other  muscles  of  the  leg  also 
receive  a  few  fibres  from  the  lumbar 
roots  ;  this  participation  of  the  lum- 
bar roots  is  particularly  obvious  in 
the  case  of  the  extensor  longus 
digitorum,  the  extensor  proprius 
hallucis  and  the  inner  head  of 
gastrocnemius.  On  the  other  hand, 
the  peronei  and  the  outer  head  of 
gastrocnemius  would  appear  to  be 
almost  exclusively  supplied  by  sacral 
fibres. 

In  the  foot,  it  is  the  muscles  of 
the  internal  compartment,  the  ab- 
ductor and  the  flexor  brevis  hallucis, 
that  appear  to  receive  the  principal 
supply,  though  an  unimportant  one, 
of  lumbar  fibres.  On  the  other 
hand,  the  adductores  hallucis  and 
the  interossei  seem  to  be  entirely 
supplied  by  the  sacral  roots. 

We  thus  see  in  what  main  re- 
spects root  innervation  is  distin- 
guished from  peripheral  innervation 
in  the  lower  limb. 

Indeed,  we  often  meet  with 
lesions  affecting  the  third,  fourth  and  fifth  anterior  lumbar  roots  :  the 
symptoms  observed  are  those  of  paralysis  of  the  anterior  crural  and  of  the 
obturator,  and  we  are  at  first  somewhat  surprised  to  find  associated  there- 
with both  paralysis  of  the  tibialis  anticus  and  weakening  of  the  extensores 
digitorum,  belonging  to  the  region  of  the  sciatic.  Frequently  the  tibialis 
anticus  appears  to  be  profoundly  affected  in  lesions  connected  solely 
with  the  fourth  lumbar. 

In  the  same  way,  inverse  dissociation  is  found  in  lesions  of  the  first  and 
second  sacral  roots  ;  at  first  they  seem  to  spread  over  almost  the  whole 
region  of  the  sciatic  and  we  are  surprised   to  find  that  the  tibialis  anticus 


Fig.  313.  Fig.  3 14. 

Figs.  313  and  314. — Muscles  supplied  by 
the  first  and  second  sacral  roots.  Note 
the  almost  complete  integrity  of  the  tibialis 
anticus  and  the  partial  preservation  of  the 
extensors. 


292 


NERVE   WOUNDS 


is  not  touched  at  all,  that  some  faint  movements  of  the  extensors  are 
possible,  and  that  there  are  even  some  very  feeble  contractions  of  the  inner 
head  of  gastrocnemius  and  of  the  muscles  of  the  great  toe. 

Sensory  disturbances  of  the  first  and  second  sacral  roots  occupy  a 
broad  tract  which,  after  spreading  over  the  posterior  surface  of  the  buttock, 
extends  obliquely  to  the  external  surface  of  the  knee  and  leg,  passes  on  to 
the  anterior  surface  of  the  leg  and  covers  both  the  dorsal  surface  and  the 
plantar  surface  of  the  foot  as  far  as  the  first  intermetatarsal  space. 


Figs.  315  and  316. — Lesion  of  the  first,  second  and  third  sacral  roots.  The  anaesthetic 
region  has  been  painted  with  tincture  of  iodine.  The  lesion  of  the  third  sacral  root 
adds  to  the  topography  of  the  first  and  second,  the  inner  region  of  the  buttock  and  a  small 
postero-external  tract  on  the  thigh.  Paralysis  of  all  the  muscles  of  the  leg,  with  the 
exception  of  the  tibialis  amicus  which  is  scarcely  touched.  There  are  also  some  slight 
movements  of  the  extensor  hallucis  and  of  the  extensor  communis  ;  a  faint  suggestion 
of  contraction  of  the  inner  head  of  gastrocnemius  and  of  the  flexor  brevis  hallucis. 


In  this  same  region,  when  there  is  irritation  of  the  roots,  we  find 
hyper-aesthesia  or  the  trophic  disturbances  characteristic  of  neuritic  lesions. 

The  Achilles  reflex  (first  and  second  sacral)  is  in  every  case  abolished. 

The  third  sacral  root  is  distributed  over  the  inner  part  of  the  buttock  j 
it  descends  on  to  the  posterior  surface  of  the  thigh,  as  far  as  its  middle, 
occupying  a  triangular  tract  just  internal  to  the  region  of  the  second 
sacral. 

When    the    fourth    and   fifth    sacral    roots   are    injured,   it  results  in 


LUMBO-SACRAL   PLEXUS 


293 


Fig.  317. 

Fig.  317. — Plantar  anaesthesia  in  the 
preceding  case.  The  line  of  demarca- 
tion passes  through  the  first  intermeta- 
tarsal  space  and  the  first  interdigital 
space. 

Fig.  318. — Cutaneous  desquamation  with 
root  topography  in  irritative  lesion  of 
the  first  and  second  sacral  roots  {radi- 
culitis). 


Fig.  318. 


incontinence  of  urine  and  faeces,  due  to  paralysis  of  the  sphincters  ; 
vesical  paresis,  paralysis  of  the  levator  ani  and  of  the 
bulbo-cavernosus  and  ischio-cavernosus  muscles. 

The  patient  is  no  longer  aware  of  the  passage  of 
urine  and  faecal  matter. 

Anaesthesia  affects  the  inner  part  of  the  buttock 
and  a  tract  down  the  posterior  surface  of  the  thigh, 
which     constitutes    the    area    of    the    third    sacral,    it 

reaches  the  perineal 
and  anal  region,  the 
penis,  the  lower  part  and 
posterior  surface  of  the 
scrotum  ;  the  root  of  the 
penis  and  a  portion  of 
its  dorsal  surface  as  well 
as  the  root  and  anterior 
surface  of  the  scrotum 
receive  fibres  from  the 
twelfth  dorsal  and  the 
first  lumbar,  and  are  not 
anaesthetic. 


Fig.  319. 


Fig.  320. 

Fig.  319. — Area  of  the  third 
sacral  root.  Lesion  of  the 
sacral  canal  at  the  level  of  the 
third  spinous  process. 

FlG.  320. — Area  of  the  third, 
fourth  and  fifth  sacral  roots. 


CHAPTER   XXIII 

DIAGNOSIS  OF  THE  LESIONS  OF  THE  LUMBO 
SACRAL  PLEXUS 


The  only  important  diagnosis  to  be  studied  is  that  of  lumbo-sacral 
hematomyelia.  Indeed,  these  lesions  are  not  uncommon  in  injuries  of  the 
lumbar  region  :  wounds  from   bullets  or  shell  splinters,  fractures  of  the 

vertebral  column,  lumbar 
contusions ;  they  may  even 
result  from  the  explosion  of 
a  shell  or  a  mine  close  at 
hand  ;  they  are  paralyses, 
probably  caused  by  compres- 
sion and  sudden  decompres- 
sion, and  accompanied  by 
slight  medullary  hemorrhage 
or  air-emboli. 

Hematomyelia  of  the 
lumbo-sacral  enlargement  has 
a  somewhat  analogous  symp- 
tomatology to  the  lesions 
of  the  plexus.  It  pro- 
duces flaccid  paralysis  accom- 
panied by  muscular  atrophy 
and  reaction  of  degeneration 
resulting  from  lesion  of  the 
cells  of  the  anterior  horns  of 
the  cord  ;  this  paralysis  is 
distributed  like  root  paralysis, 
for  each  motor  root  corre- 
sponds exactly  to  a  .cord 
segment. 

As  a   result  of  lesion   of 
the  posterior  horns,  they  are 
accompanied  by  sensory  disturbances,  the  topography  of  which  is  almost 
the  same  as  that  of  root  anaesthesia. 

Diagnosis,  however,  is  possible  as  a  rule. 

In  the  first  place,  it  depends  on  the  site  of  the  wound  ;  for  whereas 
the  cauda  equina  descends  into  the  canal,  from  the  third  lumbar  vertebra 


Figs.  321  and  322. — Slight  hematomyelia  affecting 
chiefly  the  left  lumbar  segments  and  leaving 
untouched  the  sacral  segments.  Characterised 
mainly  by  anaesthesia  to  heat  and  cold  ;  thermal 
sensations  are  scarcely  perceived  at  all  ;  but  cold 
and  pin-prick  cause  a  very  painful  sensation 
which  the  patient  compares  to  burning. 


LESIONS   OF  THE   LUMBO-SACRAL   PLEXUS        295 


to    the  second  sacral,  the    lumbar  enlargement  of  the  cord    corresponds 
rather  to  the  first  and  second  lumbar  vertebrae. 

On  the  other  hand,  hematomyelia  as  a  rule  is  a  more  diffused  process, 
producing  a  topography  less  clearly  circumscribed  than  in  root  lesions. 
Paralysis,  like  anaesthesia,  is  not  often  restricted 
to  a  very  clearly  circumscribed  region,  it  en- 
croaches slightly  upon  the  neighbouring  regions, 
or  else  it  does  not  affect  certain  muscles  or  certain 
cutaneous  zones  in  the  attacked  region,  thus 
indicating  the  unequal  distribution  of  the  hemor- 
rhagic focus.  It  is  likewise  rather  rare  for  dis- 
turbances to  be  strictly  unilateral,  generally  there 
are  to  be  found  on  the  healthy  side  some  motor 
or  sensory  disturbances  showing  a  certain  degree 
of  bilateral  spread  of  the  hemorrhagic  process. 

Finally  it  must  be  remembered  that  hema- 
tomyelia is  almost  always  localised  in  the  grey 
matter  of  the  cord  ;  it  attacks  chiefly  the  anterior 
and  posterior  horns  of  the  cord,  scarcely  touching 
at  all  the  layer  of  white  matter. 

Whilst  a  lesion  of  the  anterior  horns  is 
shown  by  the  flaccid  and  atrophic  paralysis 
which  always  indicates  lesion  of  the  lower  motor 
neurone,  a  lesion  of  the  posterior  horns  gives  rise 
to  a  very  important  and  wholly  characteristic 
symptom :  the  dissociation  of  sensibility.  In 
lumbar  hematomyelia  we  often  find  anaesthesia 
to  painful  and  thermal  stimuli  (posterior  horns) 
contrasting  with  the  relative  integrity  of  tactile 
sensibility  and  above  all  with  the  preservation 
of  deep  sensibility  (posterior  columns). 

The  clear  dissociation  of  sensibility,  as  in 
syringomyelia  constitutes  a  pathognomonic  sign 
of  hematomyelia  :  no  peripheral  or  root  lesion 
is  capable  of  producing  it. 

In  some  cases  we  may  observe  even  more 
systematised  dissociations.  For  instance,  we  may 
find  that  sensibility  to  pain  is  retained,  whereas 
sensibility  to  heat  and  cold  is  manifestly  lessened  ; 
frequently  heat  and  especially  cold  are  not  clearly 
perceived  but  give  rise  to  a  painful  sense  of  burning  instead. 

Lastly,  in  slight  cases  of  hematomyelia,  the  cord  lesion  may  rev  eal 
itself  simply  by  hyper-aesthesia  to  pin-prick,  to  heat  and  to  cold,  thus 
causing  a  painful,  widely  diffused  and  persistent  sensation. 

The  prognosis  of  hematomyelia,  especially  of  slight   hematomyelia,  is 


Fig.  323. — Lumbar  hema- 
tomyelia. Hypi>-a.-sthesia. 
On  the  right,  a  region 
resembl/ng  the  distribu- 
tion of  the  lower  lumbar 
and  the  sacral  roots.  On 
the  left,  a  region  resem- 
bling the  distribution  of 
the  first  and  second  lum- 
bar, and  of  the  fifth  lum- 
bar, the  first  and  second 
sacral.  Dissociation  of 
sensibility.  Thermal  and 
painful  anaesthesia.  Rela- 
tive conservation  ot  tac- 
tile sensibility  ;  almost 
complete  integrity  ot 
sensibility  to  pressure  and 
of  the  other  deep  sensi- 
bilities. 


296  NERVE   WOUNDS 

generally  far  more  favourable  than  that  of  root  lesions.  In  a  few  months, 
even  sometimes  in  a  few  weeks,  we  see  a  progressive  diminution  of  the 
region  of  paralysis  and  anaesthesia. 

Improvement  often  passes  on  to  complete  cure,  but  anaesthesia  may 
persist,  or  even  more  commonly,  well-defined  paralysis. 


PART    IV 
CONCLUSIONS 

CHAPTER   XXIV 

PROGNOSIS  AND  TREAMENT  OF  PERIPHERAL 
NERVE   LESIONS 

At  the  present  time,  basing  our  opinion  on  a  very  large  number  of 
observations  made  since  the  beginning  of  the  war,  we  are  justified  in 
affirming  that  the  prognosis  of  peripheral  nerve  lesions  is  on  the  whole 
favourable. 

Every  peripheral  nerve  affected  by  traumatism  tends  to  regenerate, 
provided  the  general  condition  of  the  patient  enables  him  to  contribute 
towards  this  restoration.  It  is  this  wonderful  aptitude  of  the  nerves 
towards  regeneration  by  fresh  shoots  from  the  axis-cylinders,  that  explains 
the  considerable  number  of  spontaneous  cures. 

Surgical  intervention  itself  has  no  other  aim  than  to  favour  this  natural 
regeneration,  by  suppressing  the  obstacle  to  the  progress  of  the  nerve 
fibres  and  bringing  about  coaptation  of  the  segments  of  the  divided 
nerve,  i.e.  of  the  central  segment  containing  the  nerve  fibres  along  with 
the  peripheral  segment,  the  empty  sheaths  of  which  are  alone  capable  of 
guiding  the  axis-cylinders  in  their  regeneration. 

The  wide-spread  destruction  of  the  peripheral  nerves  is  also  reparable 
by  nerve  grafting  which  reconstructs  the  anatomical  continuity  of  the 
supporting  tissues,  the  conductor  of  the  regenerating  fibres. 

According  to  our  personal  statistics,  we  may  estimate  at  between  sixty 
and  seventy  per  cent,  approximately  the  number  of  spontaneous  regenera- 
tions without  surgical  intervention  ;  at  the  same  time,  there  are  a  certain 
number  of  these,  between  ten  and  twenty  per  cent.,  which  in  our  opinion 
would  have  gained  by  such  intervention  ;  a  simple  liberation  or  even  a 
nerve  suture,  if  performed  at  the  right  time,  would  in  all  probability  have 
permitted  of  a  more  rapid  and  complete  restoration. 

We  are  now  speaking  of  cases  in  which  the  neurological  examination, 
made  only  from  eight  to  ten  months  after  the  wound,  shows  a  nerve 
manifestly  to  be  on  the  way  to  recovery,  though   this  may  be  slow  and 


298  NERVE   WOUNDS 

incomplete  ;  naturally  in  such  cases  one  hesitates  to  have  recourse  to  any 
intervention  not  absolutely  necessary  and  which  would  compel  the  patient 
to  begin  all  over  again  the  regenerative  process  painfully  carried  through 
in  the  course  of  the  preceding  months.  After  all,  such  cases  should 
become  exceptional  if  the  neurological  examination  is  always  made  in 
good  time. 

Consequently  those  cases  of  nerve  lesion  that  necessitate  surgical 
intervention,  whether  liberation  or  suture,  do  not  appear  to  be  more  than 
thirty  or  forty  per  cent. 

Results  naturally  vary  according  to  the  intervention  practised.  Still, 
we  may  lay  it  down  as  a  general  principle  that  the  liberation  of  a  nerve, 
when  this  is  indicated,  should  always  be  successful  ;  if  such  is  not  the 
case,  it  is  because  resection  and  suture  were  necessary,  and  intervention 
should  be  resumed. 

The  results  of  nerve  suture  have  been  very  much  questioned  ;  to  us, 
however,  there  does  not  appear  to  be  any  doubt  at  all  on  the  matter. 
Nerve  suture  practised  under  favourable  conditions  almost  invariably 
succeeds.  Out  of  one  hundred  and  eight  cases  of  nerve  suture  or  grafting 
which  we  have  been  able  to  follow  up,  there  are  only  fourteen  failures  ; 
i.e.  fourteen  cases  in  which  there  appears  no  sign  of  regeneration  of  the 
peripheral  segment  ;  all  the  rest  are  on  the  way  to  a  more  or  less  rapid 
and  complete  regeneration,  and  consequently  warrant  us  in  looking 
forward  to  their  cure  :  up  to  date  we  have  had  twenty-two  cases  of 
practically  complete  restoration.* 

Accordingly  we  may  estimate  at  from  twelve  to  fifteen  per  cent, 
approximately  (12*9  per  cent,  in  our  statistics)  the  cases  of  failure  after 
nerve  suture. 

We  must  add  that  the  statistics  here  given  do  not  deal  solely,  as  one 
might  think,  with  only  favourable  cases,  operated  on  at  the  right  time  and 
under  favourable  conditions,  but  with  all  the  cases  we  have  investigated. 

Early  intervention  does  not  appear  to  be  an  indispensable  condition  ; 
we  have  witnessed  the  success  of  nerve  sutures  practised  thirteen  and 
fifteen  months  after  the  wound  ;  it  is  quite  possible  that  suture  might 
successfully  be  attempted  long  after  this  period.  Nevertheless,  there  can 
be  no  doubt  but  that  early  sutures  are  followed  by  more  rapid  regeneration. 

A  favourable  prognosis  for  peripheral  nerve  lesions  is,  as  we  see,  con- 
firmed by  these  figures.  More  than  half  the  patients  are  cured  spon- 
taneously ;  almost  all  surgical  interventions  are  attended  with  success. 

The  number  of  irreparable  nerve  wounds  would  certainly  appear  not 
to  exceed  from  eight  to  ten  per  cent. ;  either  because  surgical  intervention 
has  encountered  insuperable  difficulties  or  because  the  general  condition 

*   Most  of  these  cases  were  operated   on  at  Le  Mans  by  M.  Delageniere,  whom  we  take  this 
opportunity  of  thanking  for  his  valuable  advice. 


TREATMENT   OF   PERIPHERAL   NERVE   LESIONS     299 

of  the  patients  has  either  annulled  or  made  difficult  the  work  of  regenera- 
tion. Amongst  the  factors  contributing  to  failure,  mention  must  be  made 
of  alcoholism  ;  two  cases  of  nerve  suture  carried  out  under  the  best  of 
conditions  were  succeeded  by  no  sign  of  regeneration  whatsoever  in 
patients  manifestly  alcoholic. 

The  figures  we  have  cited,  more  particularly  the  proportion  of  successes 
registered  after  nerve  suture,  may  perhaps  seem  surprising.  Tbey  are 
nevertheless  correct,  and  may  be  compared  with  those  of  other  neurological 
centres,  particularly  that  of  Professor  Dejerine  at  the  Salpetrierc. 

If  they  appear  to  clash  with  other  published  statistics,  we  affim  that 
this  is  because  people  are  always  too  precipitate  in  speaking  of  the  failure 
of  surgical  intervention.  It  must  not  be  forgotten  that  the  regeneration 
of  a  nerve  is  invariably  an  extremely  prolonged  task.  Under  the  most 
favourable  conditions,  and  in  the  case  of  young  patients,  the  progress  of 
the  axis-cylinders  is  not  more  than  one  to  two  millimetres  per  day  ;  the 
appearance  of  the  first  voluntary  movements  also  takes  place  long  after  the 
penetration  of  the  axis-cylinders  into  the  paralysed  muscle.  Consequently, 
to  affirm,  three,  four,  or  six  months  after  nerve  suture,  the  failure  of  inter- 
vention because  no  movement  shows  itself,  is  a  serious  error,  to  be  attri- 
buted to  nothing  else  than  impatience  on  the  part  either  of  the  observer 
or  of  the  patient  ;  besides,  motor  restoration  is  invariably  the  most  tardy 
of  all. 

We  shall  realise  much  more  correctly  the  progress  made  if  we  try,  on 
the  contrary,  to  discover  the  sensory  signs  of  regeneration  ;  the  sensibility 
of  the  nerve  to  pressure  and  its  characteristic  formication,  the  sensibility 
of  muscular  bellies,  cutaneous  paresthesia,  etc. 

The  sign  of  formication  is  here  specially  important,  since  it  enables  us, 
after  a  few  weeks,  to  note  the  appearance  of  the  axis-cylinders  beyond  the 
suture,  and  to  follow  their  progressive  advance  in  the  peripheral  trunk. 
It  permits  not  only  the  observer  but  also  the  patient  to  follow  the  work  of 
restoration  step  by  step  ;  it  proves  to  him  the  success  of  surgical  inter- 
vention, gives  him  confidence  and  patience,  and  thus  becomes  an  important 
moral  factor  in  the  cure. 


CHAPTER  XXV 
SURGICAL  TREATMENT 

I.— INDICATIONS   FOR  OPERATION 

To  lay  down  the  indications  for  operation  is  assuredly  the  most  delicate 
problem  in  war  neurology. 

Apart  from  a  few  special  cases,  it  would  appear  as  though  we  ought 
to  reject  the  principle  of  prompt  and  systematic  intervention  for  every 
wound  of  the  peripheral  nerves. 

Indeed,  we  have  seen  that  the  majority  of  nerve  lesions,  about  sixty 
or  seventy  per  cent.,  were  susceptible  of  spontaneous  regeneration  ;  even 
the  diagnosis  of  complete  interruption  of  a  nerve  trunk  does  not  inevitably 
imply  the  necessity  of  intervention,  for  even  in  these  cases  spontaneous 
regeneration  is  often  possible. 

The  only  fact  which  necessarily  calls  for  intervention  is  the  absence 
of  regeneration  of  the  peripheral  segment,  or  else  the  defective,  difficult 
or  partial  character  of  the  regeneration. 

Consequently,  before  deciding  to  operate,  we  must  make  absolutely 
certain,  by  successive  examinations,  that  regeneration  is  either  not  taking 
place  at  all  or  is  progressing  badly.  It  is  scarcely  ever  possible  to  obtain 
such  certainty  in  less  than  two,  three  or  even  four  months  after  the  wound. 

Besides,  as  we  have  already  seen,  this  delay  as  a  rule  is  in  no  way 
prejudicial  to  the  success  of  intervention. 

Manifestly  this  recommendation  must  not  be  accepted  as  absolute  ; 
there  are  cases  in  which  prompt  operation  is  necessary,  especially  in  simple 
compression  and  severe  neuritis. 

I. -TIME  OF  INTERVENTION 

We  discovered  that  two  or  three  months  at  least  were  often  necessary 
to  establish  the  necessity  of  intervention. 

On  the  other  hand,  an  operation  must  be  carried  out  as  soon  as 
possible,  once  its  necessity  has  been  recognised. 

Regeneration  is  assuredly  more  rapid  and  easy  when  the  operation  is 
not  delayed  too  long. 

Still,  it  must  not  be  forgotten  that,  even  twelve  or  fifteen  months  after 
nerve  interruption,  suture  may  be  performed  successfully. 


SURGICAL   TREATMENT  301 


II.— CHOICE    OF    INTERVENTION 

As  clinical  reasons  alone  can  indicate  the  necessity  of  intervention,  so 
it  is  mainly  by  a  clinical  examination  that  the  nature  of  the  intervention 
will  be  decided. 

No  intervention  must  take  place  until  we  have  obtained  every  item  of 
clinical  information  to  prove  the  existence  of  complete  interruption  or 
simple  compression,  of  a  total  lesion  or  a  partial  change,  of  regeneration 
that  is  non-existent  or  is  simply  difficult  to  effect. 

Assuredly  this  clinical  information  will  not  always  suffice  in  deciding 
upon  a  suture  or  a  liberation  ;  account  must  naturally  be  taken  of  the 
lesions  encountered  during  intervention  as  well  as  of  operative  possi- 
bilities ;  though  clinical  reasons  above  all  others  are  the  most  important. 
A  thorough  preliminary  examination,  or  rather  a  series  of  minute  examina- 
tions, almost  invariably  enable  one  to  decide  upon  the  kind  of  intervention 
necessary. 

Moreover,  information  given  by  the  anatomical  state  of  the  nerve  is 
often  somewhat  difficult  to  interpret. 

Evidently  no  hesitation  will  be  felt  in  the  presence  of  a  complete 
section,  of  a  particularly  dense  nerve  cicatrix  or  of  bulky  neuromata. 

It  must  always  be  remembered  that  all  neuromatous  formations  imply 
the  existence  of  an  obstacle,  above  which  the  regenerated  fibres,  unable  to 
reach  the  peripheral  segment,  shrivel  up.  It  is  therefore  always  necessary 
to  remove  the  obstacle  by  liberation  if  it  is  external  to  the  nerve  and  by 
resection  if  it  is  interstitial. 

In  many  cases,  however,  less  clearly  characterised,  anatomical  examina- 
tion of  the  nerve  is  not  sufficient  to  solve  the  problem. 

Indeed,  it  is  a  matter  of  absolute  importance  to  find  out  if  there  is 
simple  extrinsic  compression  or  an  interstitial  obstacle  ;  if  the  lesion  has 
destroyed  the  continuity  of  the  nerve  fibres  or  has  changed  them  locally  ; 
if  the  obstacle  is  permeable  or  not  to  the  regenerating  nerve  fibres.  This 
information  cannot  be  supplied  by  anything  but  a  clinical  examination. 

In  this  connection,  however,  the  electrical  and  histological  examina- 
tion of  the  nerve,  exposed  during  the  operation,  has  been  recommended. 

Direct  electrical  examination  of  the  nerve  trunk  has  been  carried  out 
by  P.  Marie,  H.  Meige,  and  Gosset  by  using  a  small  sterilisable  metallic 
electrode*  which  allows  of  separate  excitation  of  the  different  fasciculi  of 
the  nerve  above  and  below  the  lesion.  We  may  thus  ascertain  if  these 
fasciculi  have  remained  excitable. 

Evidently  this  method  is  capable  of  affording  very  important  informa- 
tion, though  of  itself  alone  it  is  insufficient.  It  proves  very  clearly  that 
certain  fasciculi,  or  even  the  entire  nerve,  have  not  been  touched  by  the 

*   Pierre  Marie,  Bull.  Jc  VAcad,  de  Med.,  meeting  of  9  February,  191  5. 


302  NERVE   WOUNDS 

lesion  ;  in  addition,  it  has  undoubted  value  by  reason  of  the  positive 
information  it  gives.  The  negative  information,  however,  has  not  the 
same  value  ;  electrical  stimulation  of  the  nerve  shows  no  reaction  what- 
soever and  consequently  has  no  value  at  all  if  it  acts  upon  sensory  fasciculi 
or  upon  motor  fasciculi  in  course  of  regeneration.  We  cannot  therefore 
conclude,  because  a  nerve  or  a  nerve  fasciculus  is  incapable  of  being 
excited,  that  it  is  not  in  course  of  spontaneous  regeneration  ;  electrical 
excitability  of  the  nerve  is,  as  we  know,  one  of  the  most  tardy  signs  of 
regeneration  ;  the  sensibility  of  the  nerve  to  pressure,  formication,  the 
return  of  tone,  the  appearance  of  paresthesia  are  earlier  signs.  Thus,  by 
taking  account  only  of  electrical  inexcitability,  we  should  run  the  risk  of 
resecting  and  suturing  healthy  sensory  fasciculi  and  motor  fasciculi,  well 
advanced  in  regeneration. 

Histological  examination  of  the  nerve,  by  an  actual  operative  biopsis, 
has  been  recommended  by  A.  Sicard.*  This  method  consists  in  removing 
a  few  particles  of  nerve  tissue  from  the  peripheral  segment  below  the 
lesion  and  there  trying  to  discover,  from  rapid  staining  with  osmic  acid, 
the  existence  of  myelinised  nerve  fibres. 

This  method  is  far  more  questionable  even  than  the  former  : 
i.  The  existence  of  nerve  fibres  in  the  examined  fragments  does  not 
prove  that  the  other  fasciculi  of  the  nerve  are  in  the  same  condition  ;  the 
absence  of  fibres  in  the  fasciculus  examined   is  no  proof  that  the  other 
fasciculi  are  also  affected. 

2.  Staining  with  osmic  acid  reveals  only  myelinised  fibres ;  now  the 
young  fibres  in  course  of  regeneration  consist,  at  the  outset,  of  the  axis- 
cylinder  alone. 

3.  It  is  to  be  regretted  that  we  cannot  obtain  any  certainty  of  the 
integrity  of  a  nerve  fasciculus  except  by  subjecting  it  to  the  traumatism  of 
a  biopsis  and  suppressing  some  of  its  fibres. 

As  regards  the  process  of  injecting  methylene-blue  into  or  above  the 
neuroma,  in  order  to  demonstrate  its  permeability  to  the  axis-cylinders, 
this  would  seem  to  be  a  very  doubtful  course  to  adopt. 


II.— SURGICAL  INTERVENTIONS 

There  are  but  three  interventions  possible  on  a  nerve  trunk  : 
Liberation ; 
Suture ; 
Grafting. 

1.  Liberation. — Liberation  consists  essentially  in  dissection  of  the  nerve 
and  in  ablation  of  the  causes  of  compression,  bony  callus,  fibrous  tissue  or 
cicatricial  bands. 

The  operation  is  a  very  delicate  one,  and  is  really  satisfactory  only  if 

*  A.  Sicard,  Imbert.  Jounlan,  and  Gastaud,  Acad,  de  Med.,  meeting  of  16  February,  19 15. 


SURGICAL   TREATMENT  303 

we  succeed  in  completely  stripping  bare  the  nerve  cord  and  Liberating 
from  all  adhesions  the  delicate  neurilemma  sheath  surrounding;  it. 

This  intervention  is  really  permissible  only  when  it  restores  a  mobile, 
free  and  supple  nerve,  in  the  interior  of  which  there  is  found  no  obstacle 
to  regeneration. 

It  is  naturally  indicated  in  all  cases  of  simple  compression  :  it  may  be 
practised  in  cases  of  ordinary  neuritis.  Its  success  is  all  the  more  likely 
when  intervention  is  prompt. 

As  a  rule,  liberation  of  the  nerve  is  ineffective  in  cases  of  severe  lesions 
of  the  nerve  trunk  along  with  rupture  of  the  laminated  sheath,  cicatricial 
nerve  keloid  and  formation  of  exuberant  neuromata ;  in  these  cases,  either 
the  cicatricial  obstacle  is  permeable  to  the  regenerating  axis-cylinders  and 
intervention  is  then  useless,  or  else  the  obstacle  does  not  allow  of  the 
passage  of  the  axis-cylinders  and  liberation  will  not  make  it  permeable. 

Seldom  does  liberation  succeed  in  severe  and  long-standing  cases  of 
neuritis.  Almost  always  in  such  cases  there  are  interstitial  lesions  of  the 
nerve,  and  on  these  liberation  has  no  effect. 

In  all  doubtful  cases,  remember  that  a  good  complete  suture  is  far  better 
than  a  bad  liberation. 

2.  Suture. — Nerve  suture  is  indicated  in  all  cases  of  complete  inter- 
ruption of  nerve  fibres  where  no  satisfactory  regeneration  has  taken  place. 

There  is  but  one  way  of  suturing  a  nerve  trunk,  and  that  is  by 
bringing  into  contact  the  healthy  extremities  of  the  interrupted  nerve 
trunk  and  sewing  them  end  to  end. 

Suture,  then,  essentially  presupposes  resection  of  the  cicatricial  obstacle 
and  of  all  tissues  which  might  impede  the  progress  of  the  axis-cylinders. 

We  should  bring  into  contact  with  each  other  a  central  end,  containing 
healthy  and  regularly  arranged  axis-cylinders,  and  a  peripheral  end,  offering 
for  the  growth  of  nerve  fibres  supple  and  readily  permeable  sheaths. 

Any  suture  that  does  not  fulfil  these  conditions  is  defective  and  almost 
invariably  condemned  to  failure.  All  the  same,  if  necessary,  we  may 
sew  a  supple  peripheral  segment  on  to  a  neuroma  richly  supplied  with 
axis-cylinders  ;  but  we  risk  serious  disturbances  in  the  arrangement  of 
the  nerve  fasciculi,  the  systematisation  of  which  is  thus  left  to  chance. 

On  the  other  hand,  by  suturing  the  two  healthy  segments,  if  we  very 
carefully  avoid  all  torsion  of  the  nerve,  we  put  exactly  in  their  right  places 
the  different  motor  and  sensory  fasciculi  and  do  away  with  all  risk  of 
defective  regeneration. 

Such  a  suture  almost  invariably  involves  considerable  shortening  of  the 
nerve,  a  process  which  we  shall  be  able  to  assist  by  flexion  of  the  neigh- 
bouring articulations,  as  indicated  by  Delorme. 

The  most  effective  suture  is  that  which  produces  the  best  contact  with 
a  minimum  of  traumatism  for  the  nerve  trunk.  Speaking  generally,  it  is 
better  to  content  oneself  with  a  few  stitches — silk  or  linen  thread  or  even 


304  NERVE   WOUNDS 

catgut — inserted  in  the  neurilemma.*  If  the  suture  is  tight  and  we  are 
compelled  to  go  through  the  nerve,  it  is  preferable  to  use  only  catgut, 
strong  enough  not  to  tear  and  readily  reabsorbable  so  as  to  leave  no 
element  of  irritation  in  the  middle  of  the  axis-cylinders. 

As  a  rule,  there  is  no  occasion  to  dread  secondary  rupture  after  nerve 
suture.  By  experiments  made  on  animals,  we  know  that  union  of  the 
central  and  peripheral  segments  is  extremely  rapid,  owing  to  the  prolifera- 
tion of  the  neuroglial  cells  ;  it  appears  to  take  place  from  the  fourth  day 
onwards  (Dustin). 

Lastly,  suture  must  ensure  simple  coaptation  between  the  segments 
which  it  unites ;  a  tight  suture  which  crushes  against  each  other  the 
shrivelled  nerve  extremities  exposes  the  axis-cylinders  to  the  risk  of  going 
astray  (Nageotte).  Rather  than  incur  this  risk,  it  is  better  to  leave  between 
the  segments  a  space  of  one  or  even  two  millimetres,  easily  filled  in  by  the 
neuroglial  proliferation. 

Suture  as  thus  interpreted  is  certainly  the  best  operation  for  all  serious 
nerve  lesions  in  which,  along  with  an  almost  or  wholly  complete  inter- 
ruption, there  exists  an  obstacle  to  regeneration. 

In  our  opinion,  it  may  even  be  recommended  in  certain  cases  of  grave 
neuritis  from  interstititial  lesions,  hemorrhages  or  fibrous  infiltration.  In 
these  cases  it  is  better  to  run  the  risks  of  suture  than  to  see  the  evolution 
and  prolongation — in  spite  of  a  liberation,  which,  after  all,  is  never  effica- 
cious— of  fibrous  contractions  and  trophic  disturbances  which  are  so  difficult 
to  cure. 

3.  Nerve  grafting. — When  the  distance  between  the  segments  of  the 
nerve  trunk  is  too  great  to  permit  of  direct  suture,  the  only  legitimate 
operation  is  nerve  grafting,  as  recommended  by  J.  and  A.  Dejerine  and 
Mouzon. 

This  consists  in  uniting  the  segments  of  the  interrupted  nerve  by  the 
interposition  of  fragments  removed  from  a  sensory  nerve.  The  musculo- 
cutaneous, which  to  a  considerable  length  may  be  removed  from  the  leg, 
is  the  nerve  to  which  preference  is  given. 

One,  two,  or  more  of  these  fragments,  united  in  a  bundle  by  catgut 
passed  through  them,  are  sewn  on  both  sides  to  the  central  and  peripheral 
segments.  Regeneration  would  seem  to  take  place  through  the  graft  some- 
what more  slowly  than,  though  almost  as  effectively  as,  by  direct  suture. 

All  other  grafting  processes  are  more  or  less  defective. 

Suture  by  division  into  two  is  inevitably  partial,  since  it  suppresses  part 
of  the  nerve.  In  any  case,  if  this  suture  is  practised,  it  is  always  the 
peripheral  segment  which  must  be  divided.  Division  of  the  central  end 
should  be  altogether  condemned,  since  it  inevitably  interrupts  half  of  the 
axis-cylinders.  The  divided  fragment  also  should  be  completely  detached 
and  sewn  end  to  end  with  the  two  segments  of  the  interrupted  nerve. 

*  Catgut  should  be  used  exclusively  in  nerve  suture. — (Ed.) 


SURGICAL   TREATMENT  305 

Pseudo-graftings  by  interposition  between  the  nerve  segments  of"  some 
tendon  fibres,  fragments  of  aponeurotic  sheaths,  catgut  threads  intended 
to  serve  as  conducting  wires  (?)  are  wholly  illogical  and  inevitably  con- 
demned to  failure. 

There  is  nothing  but  nerve  tissue  that  can  serve  as  a  conductor  for  regenerat- 
ing axis-cylinders. 

Defective  operations. — All  that  we  have  said  about  the  main  principles 
of  nerve  regeneration  is  sufficient  to  show  how  illogical  and  ineffective  are 
certain  methods  once  strongly  recommended. 

All  lateral  sutures  must  be  condemned  that  do  not  make  continuous 
the  axis-cylinders  of  the  central  end  and  the  empty  sheaths  of  the  peri- 
pheral end ;  lateral  implantations,  sutures  by  division  into  two  of  the 
upper  segment,  transplantations  of  one  nerve  into  the  other,  and  more 
especially  transplantations  of  a  motor  nerve  into  a  sensory  one  arc  almost 
always  useless  and  often  mischievous  operations. 

We  must  condemn  the  ablation  of  the  lateral  neuromata ;  such  inter- 
vention is  purposeless  since  it  merely  removes  the  extremity  of  the 
regenerating  nerve  fibres  above  an  interruption  without  supplying  a  guiding 
channel  for  these  fibres  ;  the  removed  lateral  neuroma  will  inevitably  form 
again  on  the  same  spot,  as  does  a  neuroma  in  the  case  of  an  amputation. 

"  Combing  "  of  the  nerve  must  also  be  condemned  ;  it  neither  liberates 
nor  restores  anything  but  merely  effects  a  chance  division  into  sections  of 
a  few  nerve  fibres,  the  regeneration  of  which  thus  becomes  a  matter  of 
uncertainty.  The  only  "combing"  which  can  be  advocated  in  some 
cases  is  the  longitudinal  incision  of  the  sheath  at  the  level  of  the  interstitial 
hematomata  occasionally  found  in  cases  of  violent  contusion. 

Partial  operations. — For  partial  lesions,  however,  we  are  sometimes 
led  to  practise  partial  operations.  For  instance,  we  may  simply  suture 
an  interrupted  bundle  of  a  partially  untouched  nerve.  Moreover,  such 
interventions  can  only  be  made  on  the  big  nerve  trunks. 

They  may  be  effected  by  cleavage  of  the  nerve  ;  its  untouched  part 
is  bent  back  loop-fashion  to  allow  of  direct  suture  of  the  segments  shortened 
by  removal. 

In  these  cases  it  is  better,  when  reuniting  the  cut  bundle,  to  have 
recourse  to  grafting,  except  in  the  case  of  the  big  nerve  trunks,  such  as 
the  sciatic. 

Isolation  of  the  nerves. — Care  must  be  taken  lest  liberated  or  sutured 
nerves  should  again  be  embedded  and  compressed  by  the  fibrous  tissue  of 
the  scar.     Several  methods  of  preventing  tin's  have  been  recommended. 

Isolation  of  the  nerve  by  an  aponeurotic  Hap,  a  muscular  bed,  a  tatty 
covering,  has  been  proposed  ;  catgut  has  been  rolled  round  the  nerve  ;  it 
has  been  enveloped  in  a  peritoneal  flap  or  a  layer  of  amnion  ;  attempts 

20 


3o6  NERVE   WOUNDS 

have  even  been  made  to  wrap  round  it  a  thin  sheet  of  aluminium  or  of 
rubber  ;  the  two  united  fragments  have  been  brought  into  a  segment  of  a 
vein  or  an  artery  ;  a  few  drops  of  gomenol  have  been  injected  around  the 
nerve.  .  .  . 

In  our  opinion,  these  practices  are  almost  always  useless,  and 
even  harmful  in  many  cases,  especially  as  regards  the  use  of  foreign 
bodies. 

It  must  be  well  understood  that  the  laying  bare  of  the  nerve  to  a 
considerable  extent  and  the  rolling  round  it  of  an  isolating  plate  of  any 
kind  involves  the  risk  of  diminishing  vascularisation  from  the  surrounding 
tissues  and  thus  compromising  regeneration. 

If  we  would  rightly  endeavour  to  do  away  with  cicatricial  fibrous 
formations  round  the  nerve,  we  must  not  forget  that  fibrous  tissue  may 
develop  at  the  expense  of  all  the  tissues  ;  muscle,  fat,  peritoneum,  amnion 
are  as  likely  to  be  transformed  into  cicatricial  tissue  as  the  connective 
tissue  itself. 

We  give  it  as  our  opinion,  therefore,  that  none  of  these  practices, 
speaking  generally,  are  to  be  adopted.  There  is  but  one  exception  to 
this  rule,  and  that  is  when  the  liberated  or  sutured  nerve  happens  to  be 
in  contact  with  bony  or  periosteal  surfaces  capable  of  involving  it 
secondarily  ;  the  most  frequent  instance  is  that  of  the  musculo-spiral 
liberated  from  the  callus  of  a  fractured  humerus. 

In  these  cases  we  can  and  ought  to  effect  isolation  of  the  nerve  in  the 
vicinity  of  callus  or  a  bony  projection  ;  the  best  method  is  certainly  the 
interposition  of  a  muscular — or  better  still  a  fatty — layer. 

But  in  all  other  cases  we  look  upon  these  proceedings  as  both  useless 
and  harmful. 

The  best  means  of  avoiding  cicatricial  fibrous  formations  is  : 

i.  To  avoid  operating  in  a  septic  area;  a  nerve  operation,  as  far  as 
possible,  should  take  place  only  after  complete  cicatrisation  of  the  wound 
and  when  all  inflammatory  reaction  is  at  an  end. 

2.  To  make  a  very  careful  hemostasis,  blood  infiltration  being  one  of 
the  main  factors  in  secondary  fibrous  formations. 

3.  To  practise  mobilisation  and  massage  of  the  cicatrix  very  carefully 
and  in  good  time. 

Alcoholisation  of  nerve  trunks  (Sicard). — The  failure  of  all  kinds  of 
treatment  and  the  continuance  of  intolerable  pain  in  certain  cases  of 
severe  neuritis,  more  especially  in  causalgia,  have  led  certain  authorities  to 
attempt  the  physiological  interruption  of  the  nerve. 

In  several  cases,  resection  and  suture  of  the  nerve  have  been  practised. 
This  succeeds  quite  well  in  serious  cases  of  neuritis  complicated  with 
trophic  disturbances,  though  failure  has  resulted  in  cases  of  causalgia  ;  the 
painful  nerve  recovers  with  extreme  rapidity,  and  the  causalgic  syndrome 
usually  reappears  after  a  few  weeks. 


SURGICAL   TREATMENT  307 

Sicard  *  has  recommended  alcoholisation  of  the  nerve  trunks,  effected 
by  injecting  above  the  lesion  a  solution  of  sixty  per  cent,  alcohol.  Tim 
injection  of  one  to  two  cubic  centimetres  is  made  in  the  nerve  itself,  after 
surgical  exposure. 

There  is  thus  produced  by  local  neuritis  a  physiological  interruption 
of  the  nerve,  which,  according  to  Sicard,  would  often  appear  to  reach  only 
the  more  fragile  sensory  fibres.  Sicard,  Pitrcs,  Grinda,  Godlewski,  Benott, 
and  Morel  state  that  they  have  been  successful  with  this  method. 

Denudation  of  the  arteries  (Leriche). — For  the  treatment  of  causalgia, 
Leriche  f  advocated  arterial  denudation  and  resection  of  the  perivascular 
sympathetic  plexus. 

This  operation  is  based  on  the  special  nature  of  the  pain  in  causalgia, 
which  is  attributed  to  irritation  of  the  sympathetic  twigs  supplied  by  the 
nerve  to  the  neighbouring  artery,  or  else  supplied  to  the  nerve  by  the 
periarterial  sympathetic  plexus. 

Causalgic  symptoms  would  appear  to  be  largely  sympathetic  in  their 
nature,  although  the  interpretation  of  these  symptoms  is  probably  some- 
what complex. 

We  rather  think  there  exists  sympathetic  irritation  of  a  reflex  nature, 
for  we  have  found  such  irritation  extend  over  almost  the  entire  region  of 
the  cervico-dorsal  sympathetic,  even  in  the  case  of  lesion  of  the  median  at 
the  wrist  (pain  over  the  entire  area  of"  the  median,  constriction  of  the 
brachial  artery,  diminution  of  the  pulse,  numbness  of  the  lower  part  of 
the  face,  and  diminution  of  sweating  at  this  level,  intermittent  redness 
of  ear  on  the  affected  side,  etc.). 

Under  these  conditions,  resection  of  the  sympathetic  plexuses  which 
surround  the  brachial  artery  would  result  in  the  suppression  of  the 
reflex  reactions  of  the  sympathetic  which  give  neuralgia  its  distinctive 
characteristics. 

At  all  events,  this  procedure  has  given  some  results  in  obstinate  cases. 
The  same  intervention  has  been  proposed  for  the  femoral  artery  in 
causalgia  of  the  lower  limb. 

Sicard,  Presse  Medicate,  I  June,  1 916. 
t    R.  Leriche,  Presse  Me'Jicale,  20  April,  1916. 


CHAPTER   XXVI 

ELECTRICAL  TREATMENT 

Electrical  treatment  may  fulfill  three  main  indications  ;  it  may  : 
i.   Maintain  contractility  of  the  paralysed  muscles. 

2.  Accelerate  regeneration. 

3.  Soothe  the  pain. 

1.  The  principal  role  of  electrical  treatment  in  paralysis  is  to  maintain 
contractility  of  the  paralysed  muscle  until  voluntary  contraction  returns. 
The  passing  of  the  current  attains  this  object  by  artificially  bringing  about 
contraction  of  the  muscle. 

The  current  to  be  used,  therefore,  is  that  which  will  most  readily  and 
with  least  intensity  produce  muscular  contraction. 

In  case  of  reaction  of  degeneration,  the  muscle  is  capable  of  being  excited 
only  by  the  galvanic  current.  There  is  polar  inversion  at  the  motor  point ; 
at  this  point,  then,  the  positive  pole  would  give  the  best  contraction  with 
the  least  intensity.  On  the  other  hand,  however,  longitudinal  excitation 
is  invariably  greater  than  excitation  through  the  motor  point  ;  it  is  almost 
always  stronger  at  the  negative  pole.  Practically,  then,  longitudinal  excitation 
by  the  negative  pole  will  be  used  to  bring  about  contraction  of  the 
muscle.  The  galvanic  current  causes  contraction  only  at  the  closing  and 
the  opening  of  the  Gurrent,  consequently  a  rhythmic  current  will  be 
utilised,  one  capable  of  producing  somewhat  slow  interruptions  (metronome 
or  undulatory). 

We  have  seen  that  the  gradual  application  of  the  current  did  not 
lessen  its  action  on  the  paralysed  muscles,  whereas  it  suppressed  the 
excitation  of  the  healthy  antagonistic  muscles.  Besides,  it  is  less  painful 
than  the  sudden  application  of  the  current,  and  permits  of  greater  intensities 
being  utilised  without  pain.  Consequently  it  will  be  a  good  thing  always 
to  effect  this  gradual  application,  either  by  employing  condensers  set  in 
series  (Lapique)  or  by  the  use  of  metallic  undulators. 

Thus  a  gentle  and  easily  borne  contraction  will  be  obtained,  limited 
almost  exclusively  to  the  paralysed  muscles  and  not  diffused  into  the 
healthy  antagonistic  muscles. 

If  there  is  no  RD,  the  muscle  can  be  excited  by  the  faradic  current  ; 
once  the  muscular  groups  can  be  contracted  under  the  faradic  current,  we 


ELECTRICAL   TREATMENT  309 

shall  be  able,  with  a  moderate  intensity,  to  utilise  this  current  in  effecting 
contraction. 

First  we  shall  utilise  the  brief  contractions,  caused  by  the  coil  interrupter ; 
then  later  we  shall  have  recourse  to  interrupted  tetanisation,  set  to  rhythm 
by  the  metronome,  or,  better  still,  by  an  undulator,  though  always  to  a  very 
slow  beat. 

In  any  case,  whether  muscular  contraction  is  caused  by  the  galvanic  or 
by  the  farad ic  current,  only  a  moderate  effort  must  be  required  from  the 
paralysed  muscle.  As  a  rule,  a  few  daily  contractions  are  sufficient  ;  cart- 
must  be  taken  not  to  overwork  a  muscle  disturbed  in  its  nutrition, 
which"  would  react  by  atrophy  to  an  electrical  treatment  which  is  too 
strong. 

2.  The  simple  passing  of  the  electric  current  appears  capable  of 
hastening  the  regeneration  of  the  nerve,  maintaining  the  nutrition  of  the 
tissues  and  facilitating  the  resolution  of  the  cicatricial  fibrous  tissues. 

For  this  purpose,  the  galvanic  current,  with  negative  pole  and  of 
moderate  intensity,  about  ten  or  fifteen  milliamperes,  is  generally  em- 
ployed. Consequently  a  simple  galvanic  bath,  lasting  from  fifteen  to 
twenty  minutes,  can  be  made  to  precede  the  few  rhythmic  excitations 
intended  to  maintain  its  contractility. 

Mention  must  also  be  made  of  the  favourable  influence  of  the  faradic 
current  of  feeble  intensity,  produced  by  stout  wire  coils.  This  current 
produces  phenomena  of  vaso-constriction  followed  by  intense,  deep  vaso- 
dilatation and  appearing  extremely  favourable  to  the  nutrition  of  the 
tissues  as  well  as  to  regeneration. 

The  rhythmic  faradic  bath  is  particularly  useful  in  the  treatment  of 
cicatricial  contractions,  of  muscular  fibrous  infiltrations,  of  cutaneous 
adhesions  and  of  the  articular  fibrous  ankyloses  produced  by  neurites,  as 
well  as  of  contractions  from  nerve  irritation. 

We  may  advantageously  bring  about  the  association  of  the  galvanic 
and  faradic  currents  under  the  galvano-faradic  form  ;  this  association 
allows  of  excitation  of  the  paralysed  muscle  whilst  avoiding  its  fibrous 
transformation  ;  it  is  by  far  the  best  treatment  for  muscular  atrophy. 

3.  The  galvanic  current  is  a  wonderful  pain-allaying  sedative,  though 
this  property  is  possessed  only  by  the  positive  pole.  The  negative  pole, 
on  the  other  hand,  is  an  excitant. 

This  current  is  utilised  most  frequently  in  the  form  of  positive  pole 
galvanic  baths,  with  intensities  varying,  according  to  the  case,  from  five, 
ten,  twenty,  or  even  twenty-five  milliamperes. 

Better  results  are  frequently  obtained  from  prolonged  baths  of  extremely 
feeble  intensity  ;  for  instance,  with  three  and  four  milliamperes  lasting 
several  hours  we  have  obtained  sedative  results  that  shorter  baths  of  greater 
intensity  could  not  have  given. 

Ionization. — Salicylated  or  iodised  ionization   has  been  employed  with 


310  NERVE   WOUNDS 

widely  varying   results    in   the  treatment  of  neuritic   pains    and    fibrous 
formations. 

Some  good  results  have  been  obtained  by  ionization  (i%  KI  solution, 
negative  pole)  recommended  by  Bourguignon.  The  diminution  of  pain 
effected  is  sometimes  remarkable,  though  inconstant  and  often  fleeting  ; 
the  lessening  of  fibrous  griffes  and  muscular  contractions  is  a  more  constant 
result. 

Diathermy. — Diathermy  may  also  be  serviceable  in  painful  and  sclerosing 
neuritis,  and  in  states  of  ischaemia  accompanied  by  fibrous  transformation. 

Radiotherapy. — Radiotherapy  is  often  very  useful  in  the  treatment  of 
painful  neuritis.  The  results  we  have  obtained  confirm  the  statistics 
published  by  Cestan  and  Descamps  ;  *  though  in  our  opinion  radiotherapy 
has  acted  rather  upon  violent  neuralgias  of  a  causalgic  type  than  upon  the 
duller  pains  of  nerve  irritation.  We  have  seen  cures  effected  more 
especially  in  several  cases  of  causalgia  of  the  median  nerve  ;  though 
frequently  the  violent  painful  paroxysms  alone  have  disappeared  whilst 
the  dull  pains  continued. 

Improvement  is  sometimes  shown  after  the  first  treatment ;  in  other 
cases,  it  appears  only  ofter  seven  or  eight  treatments. 

It  is  no  rare  occurrence  to  find  a  momentary  recrudescence  of  the  pain, 
a  possibility  of  which  the  patient  must  be  warned. 

Radiotherapy  may  take  place  either  on  the  nerve  lesion  itself  and  the 
course  of  the  affected  nerve  or  on  the  roots  and  spinal  ganglia  which 
supply  the  nerve.  On  this  point  we  are  unable  to  afford  any  precise 
indication,  for  each  of  these  methods  has  given  favourable  results  after  the 
other  has  failed. 

It  is  probable  that  radiotherapy  applied  to  the  lesion  acts  on  the 
inflammatory  element  in  the  nerve,  interstitial  infiltration  and  connective 
tissue  proliferation  caused  by  irritation  ;  radiotherapy  applied  to  the  ganglia 
and  roots  would  seem  to  be  indicated  when  the  pain  results  from  the  state 
of  reflex  hyper-excitability  of  the  ganglion  cells  which  appears  to  be  present 
in  causalgia. 

MECHANOTHERAPY— MASSAGE— GYMNASTICS-PROSTHESIS 

However  great  the  therapeutical  resources  of  electricity  in  all  its  forms, 
we  must  not  forget  that  massage  and  mechanotherapy  are  absolutely 
necessary  to  supplement  them. 

To  maintain  the  contractility  of  a  paralysed  muscle,  to  prevent  its 
fibrous  transformation,  massage  is  perhaps  as  important  as  electrotherapy. 
Daily  massage  should  be  given  to  every  paralysed  muscle. 

*   R.  Cestan   and    Descamps.      Radiotherapy  in  the  treatment  of  certain  traumatic  lesions  of 
the  nervous  system.      Prcssc  Me'JicaU;  25  November,  191 5. 


ELECTRICAL   TREATMENT  311 

A  fortiori  massage  is  indispensable  in  nerve  irritations  that  have  a 
tendency  to  fibrous  contraction  of  the  muscle,  to  cutaneous  adhesions  and 
to  articular  sclerosis  ;  it  must  be  given  in  spite  of  the  pain,  unless  this 
latter  is  really  intolerable.  The  same  may  be  said  of  mobilisation  which 
should  be  practised  daily  in  cases  of  neuritis  accompanied  by  a  tendency  to 
fibrous  ankylosis.  A  great  number  of  neuritic  griffes,  of  articular  fibrous 
ankyloses  and  muscular  contractions  might  easily  be  avoided  by  daily 
mobilisation. 

In  cases  of  neuritis  both  massage  and  mobilisation  are  invariably  more 
easy  and  efficacious  as  well  as  less  painful  after  the  limb  has  been  subjected 
to  a  hot  bath,  or  better  still,  a  hot  bath  and  faradic  current  combined. 

In  addition  to  the  passive  mechanotherapy  represented  by  massage  and 
mobilisation,  we  must  also  insist  on  the  importance  of  the  active  mechano- 
therapy effected  by  gymnastics. 

This  latter  also  maintains  the  contractility  and  nutrition  of  the  paralysed 
muscles  ;  it  helps  forward  a  return  of  the  earliest  movements  after  regene- 
ration ;  it  facilitates  and  provokes  the  important  substitutionary  movements 
in  the  case  of  paralysed  muscles  ;  it  mobilises  the  articulations  and  integu- 
ments. 

Gymnastics  of  the  wounded  limbs,  in  every  form,  both  general  and 
particular,  is  thus  of  the  utmost  importance.  One  must  have  witnessed 
the  disastrous  results  of  prolonged  immobilisation  in  cases  of  peripheral 
paralysis  and  neuritis  to  understand  the  supreme  importance  of  active 
movements.  Inactivity  of  the  wounded  limbs  and  moral  inertia  of  the 
patient  form  the  main  cause  of  the  irreducible  deformities,  the  neuritic 
contractions,  the  functional  paralyses  that  accompany  or  follow  organic 
paralyses. 

Finally,  it  is  often  necessary  to  make  use  of  appliances  of  an  elementary 
prosthetic  nature,  both  in  order  to  keep  the  limb  in  its  right  place  and  to 
permit  of  its  being  used  in  a  normal  fashion  ;  this  is  principally  the  case 
with  apparatus  intended  to  correct  flexion  of  the  hand  in  musculo-spiral 
paralysis  and  also  steppage  in  paralysis  of  the  external  popliteal.  Other 
appliances  have  as  their  object  the  avoidance  of  fibrous  contractions  and 
of  the  appearance  of  griffis. 

All  these  appliances  should  be  removable  without  any  difficulty  ;  they 
may  readily  be  improvised  with  the  aid  of  elastics  or  springs. 

SCLEROLYTIC   MEDICINAL  TREATMENT 

And  lastly,  some  mention  mu->t  be  made  of  the  treatment  of  nerve 
wounds  by  thiosinamin  or  fibrolysin  (salicylate  of  thiosinamin). 

It  is  logical  to  utilise  the  sclerolytic  quality  of  thiosinamin  in  the  treat- 
ment of  the  cicatricial  fibrous  lesions  compressing  the  injured  nerve  or 
creating  an  interstitial  obstacle  to  regeneration  of  the  axis-cylinders. 


3i2  NERVE   WOUNDS 

P.  Cazamian  *  has  mentioned  good  results  thereby  ;  in  several  instances 
he  would  appear  to  have  effected  the  disappearance  of  the  nerve  tumour 
and  also  a  certain  functional  improvement. 

The  following  formula  may  be  utilised — 

Thiosinamin 15  grammes, 

Antipyrin ....        7*5  grammes, 

Distilled  water q.s.  to  150  grammes, 

in  subcutaneous,  or  better  still,  intra-muscular  injections.  Twenty-five  or 
thirty  consecutive  injections  in  doses  of  two  cubic  centimetres,  either  daily 
or  every  other  day. 

Thiosinamin  would  seem  to  be  specially  indicated  in  syndromes  of 
compression,  neuromata  of  attrition  and  neuritic  types,  where  fibrous 
infiltration  of  the  nerve,  being  interstitial,  is  inaccessible  to  surgical  treat- 
ment ;  it  would  also  appear  as  though  it  had  a  favourable  action  on  the 
fibrous  sequelae  in  cases  of  nerve  irritation,  which  are  so  difficult  to 
mobilise  and  require  so  long  a  time. 

*  Cazamian.     Presse  Me'dicale,  11  November,  191 5. 


INDEX 


Action,  polar,  in  electro-physiology,  49 
Alcohol,  injection  of,  306 
Amesthesia,  deep  and  cutaneous,  31-33 

chloroform,  86 

complete  ulnar,  168 

from  lesion  of  posterior  tibial,  255 

in  complete  section  of  ulnar,  142 

in  lumbar  hematomyelia,  295 

in  musculo-spiral  paralysis,  107 

in  section  of  circumflex,  204 

of  cutaneous  area,  166 

of  external  cutaneous  nerve  of  thigh, 
277 

of  hand,  193 

peripheral,  92 

segmentary,  93,  97 

thermal,  78 
Andre-Thomas,  xii,  75 
Anterior  crural  nerve, 

collateral  and  terminal  branches,  268- 
271 

diagnosis  of  paralysis  of,  273 

paralysis  of,  271-272 
Anterior  tibial  nerve,  paralysis  ot,  247-248 
Aponeuroses,  29 
Apparatus,  Sollier's,  130 

of  Leri,  265 

of  Le>i  and  Dagnan-Bouveret,  131 

of  Marie  and  Meige,  265 

of  Mauchet  and  Anceau,  131 

of  Robin-Chiray,  265 
Appendages,  skin,  29 
Aran-Duchenne  syndrome,  218 
Arteries,  denudation  of,  307 
Athanassio-Benisty,  xii,  73,  77,  82,  191 
Atropy,  massive,  30 

muscular,  21 


I! 


Babinski,  xii,  40,  82,  86,  S8,  166 

Benoit,  307 

Bergonie,  59 

Bielchowski,  method  of,  13 

Bordier,  59 

Bourguignon,  5c,  55,  310 


Brachial  plexus,  209 

branches  of,  212-214 

connexions  of,  2 1 1 

lesions  of,  214-215 

primary  and  secondary  trunks,  210 

radicular  syndromes  (roots  and  primary 
trunks),  215-224 
Broca,  xii 


Cardot,  49 

Causalgia,  66,  1 87—19 1 

Cazamian,  312 

Cestan,  310 

Charcot  clinic,  vii 

Clironaxie,  53-59 

Chronaximetrc  of  Lapicque,  57-58 

Circumflex  nerve,  201 

branches,  202-203 

paralysis  of,  203-204 

sensory  disturbances  in  paralysis  of,  204 
Claude,  xii,  82,  176,  181,  195 
Club-foot,  88,  90 
Cluzet,  55 

Compression  of  nerve,  2 
Contractility,  mechanical,  of  muscle,  23 
Contraction,  fibrous,  of  muscles,  24 

club-foot  from,  90 

from  nerve  irritation,  73 
Contracture,  83 

from  neuritis,  88-91 

functional,  86,  91 

of  hand  in  flexion,  84 

of  interossei  and  hypothenar  eminence, 

Contusion  ot  nerve,  2 
Cruveilbier,  231,  239 

Current,  faradic,  37-40 
galvanic,  40-45 


1) 


Decalcification,  30 

Degeneration,  Wallerian,  5,  13,  61,  74 

Dejerine,  xii,  3,   11,  14,  15,  21,  23,  33,  60, 

62,  65,   117,   147,   159,    160,  180,  188, 

189,  245,  246,  255,  304 


3H 


INDEX 


Delherm,  40 
Delorme,  302 
Descamps,  310 

Desquamation,  cutaneous,  310 
Diagnosis  of  nerve  lesions,  15 
Diathermy,  310 
Disturbances,  cutaneous,  25 

thermal,  28 

vaso-motor,  27 
Doumer-Huet,  longitudinal  reaction  or',  45 
Dubois,  93 

Duchenne  of  Boulogne,  xii,  37,  39,  149 
Dupuytren's  contracture,  70,  156,  157 
Dustin,  304 


Electrical  treatment  in  paralysis,  308- 

309 
Engelmann,  53 
Erb,  paradox  of,  39 
Erb-Duchenne  syndrome,  216 
Examination,  faradic,  37-40 

galvanic,  40-45 
Excitability,  latent  faradic,  40 
Excitation,  selective,  of  paralyzed  muscles, 

58-59 
External  cutaneous  nerve  of  thigh,  277-278 
External  plantar  nerve,  241 
External  popliteal  nerve,  233 

clinical  forms  of  paralysis  of,  245 

collateral  and  terminal  branches,  234- 
237 

motor  syndrome,  242-243 

paralysis  of,  242 

sensory  syndrome,  244 

trophic  and  vaso-motor  syndrome,  244 
External  saphenous  nerve,  257 


Fibrous  infiltration  of  muscles,  70 
Foix,  xii,  49 
Formication,  18 

provoked  by  pressure,  34 
Froment,  xii,  82,  86,  166 


Galvano-tonus,  52 

Genito-crural  nerve,  lesions  of,  279 

Glioma,  1,  4,  9-1 1,  15 

Glossy-skin,  72,  97 

Godlewski,  307 

"Goniometer,"  19 

Gosset,  301 

Grafting  of  nerve,  304 

Granular  bodies,  5 

Griff e,  19,  24,68-69,96,98,145-169,255, 

257,  3io»  311 
Grinda,  307 
Gymnastics,  310 


H 


Hjematomyelia,  92 

Head,  79 

Henle,  loop  of,  213 

Histology,  5-15 

Hunter's  canal,  270 

Hyperesthesia,  32,  69 

Hypertonia,  73 

Hypertrichosis,  29 

Hypoassthesia,  32,  33 

Hypothenar  eminence,  atrophy  of,  13! 


Ilio-hypogastric  nerve,  280-281 
Ilio-inguinal  nerve,  280-281 
Indications  for  operation,  299 
Integuments,  examination  of,  25 
Internal  cutaneous  nerves,  205 

lesions  of,  206-207 
Internal  plantar  nerve,  24c 
Internal  popliteal  nerve,  237-239 

collateral  and  terminal  branches,  239- 
242 

grave  neuritic  type,  253 

motor  syndrome,  250-251 

sensory  syndrome,  251 

simple  neuralgic  type,  254 

slight  neuritic  type,  253 

trophic  and  vaso-motor  syndrome,  251- 
252 
Internal  saphenous  nerve,  lesions  of,  272- 

2  73. 
Ionization,    salicylated,    in    treatment    of 

neuritic  pains,  109-110 

Ischemic  paralysis,  96-98,  223 

of  upper  limb,  225-229 


Jarkovski,  40 
Jeanne,  153 
Jolly,  48 
Jumenti£,  xii 


K 


Keloids,  nerve,  v,  3,  11 


Lantermann,  incisures  of,  12,  13 

Lapicque,  53-59 

Lasegne's  sign,  70,  259 

Laugier,  49,  55-57 

Lejars,  xii 

Lemoing's  glove,  130 

Leriche,  73,  191,  192,  307 

Lesser  internal  cutaneous  nerve,  206 


INDEX 


3*5 


Letievant,  xii 

Liberation  of  nerve,  302 

Ligament,  Poupart's,  268,  272,  279 

Lumbar  roots,  289-290 

Lumbo-sacral  plexus,  282-286 

diagnosis  of  the  lesions  or,  294-296 
radicular  syndromes  of,  287-289 


M 


Marchi,  5 

Marie,  P.,  xii,  40,  49,  77,  117,  130,  301 

Massage,  310 

Mechanotherapy,  310 

Median  nerve, 

anastomotic  branch,  174 

anatomy  of  170 

causalgia  of,  187-193 

complete    paralysis    above  epitrochlear 
muscles,  178-182 

diagnosis  of  paralysis  of,  192 

dissociated  paralysis  of,  183-185 

motor  branches,  172 

motor  syndrome,  175 

neuritis  of,  185-187 

paralysis    below    epitrochlear    muscles, 
182-183 

sensory  branches,  173 

sensory  syndrome,  176 

trophic  syndrome,  177 
Median  and  ulnar  nerves,  associated  para- 
lysis of,  194-196 
Meige,  xii,  40,   73,  77,  82,  117,  130,  191, 

301 
Morel,  307 
Motor  points,  41,  42,  43 

descent  of,  52 
Mouzon,  xii,   14,   15,  21,  23,  33,  60,  65, 

117,  147,  159,  160,  189,  245,  246,  304 
Muscle,  mechanical  contractility  of,  23 

fibrous  contraction  of,  24 

sensibility  to  pressure,  23 
Muscles,  interosseous,  138 
Muscular  atrophy,  2 1 

contraction  and  hypertonia,  24 

tone,  21-22 
Musculo-cutaneous  nerve,  197 

branches,  198,  199 

isolated  paralysis  of,  248-249 

motor  and  sensory  syndromes,  200 

paralysis  of,  200 
Musculo-spiral  nerve, 

anastomotic  branches,  103 

anatomy  of,  99 

diagnosis  or    musculo-spiral    paialysis, 
126 

dissociated  paralysis  of,  1 16 

dissociation  of  extensor  communis  digi- 
torum,  1 15 

motor  branches,  102 

motor  syndrome,  104 

paralysis  above  supinator  longus,  no 


Musculo-spinal  nerve — continue  J 

paralysis     below    extensor     communis 

digitorum,  1 16 
paralysis  below  radial  extensors,  1 14 
paralysis  below  supinator  longus,  112 
paralysis  of,  104 
partial  paralysis  of  triceps,  109 
sensory  branches,  102 
sensory  syndrome,  107 
syndrome  of  compression,  118 
syndrome  of  interruption,  1 19 
syndrome  of  nerve  irritation,  121 
syndrome  of  regeneration,  1 24 
total  paralysis  of,  109 
treatment,  129 
trophic  syndrome;  108 


N 


Nageotte,  xii,  4,  9,  304 
Nails,  changes  in,  29 
Nerve,  sections  of,  1,  7 

anatomy  of,  99-103 

dissection  of,  302 

grafting,  303 

isolation  of,  305-306 

liberation  of,  302 

musculo-spiral,  99-131 

physiology  of,  104-117 

suture  of,  302 
Nerves,  musculo-spiral,  99 

anterior  crural,  268 

circumflex,  201 

external  cutaneous  nerve  of  thigh,  277 

genito-crural,  279 

ilio-hypogastric,  280 

internal  cutaneous,  205 

lesser  internal  cutaneous,  206 

median,  170 

musculo-cutaneous,  197 

obturator,  275 

sciatic,  231 

small  sciatic,  266 

ulnar,  132 
Nerve  trunks,  alcoholization  of,  306 
Neuritis,  ascending,  81-82 

paralysis,    hypertonia    and    contraction 
from,  82-91 
Neuroma,  1-4,  7-16,  35-36 
Neurotropism,  6,  7 


O 


Obturator  nerve,  275 

superficial  ami  deep  branches,  276 
CEderaa,  27 

of  hand,  108 
Operations,  defective  and  partial,  305 

choice  of,  301 

indications  for,  300 

time  of,  300 


316 


INDEX 


Pain,  spontaneous,  65 

provoked  by  pressure,  65 
Palsy,  crutch,  99 

"Saturday  night,"  99 
Paralysis,  18-30 

apparatus  for,  1 30-1 31 

central,  92 

diagnosis  of,  164-165 

from  pseudarthrosis,  95 

functional,  93-96 

hysterical,  97 

ischaemic,  96 

musculo-spiral,  104-128 

pseudo-,  95 

simple  compression  of,  144 

treatment  of,  129-130 

ulnar,  136-165 
Peripheral    nerve    lesions, 

treatment  of,  297-299 
Peroncito,  8 

Pes  equinus,  24,  69,  88,  95,  253,  259,  261 
Petres,  243,  250,  307 
Philippeaux,  xii 
Pole,  action,  50 

negative,  51 

positive,  51 
Posterior  tibial  nerve,  paralysis  of,  255 
Prosthesis,  311 
Pseudo-^r^,  164 
Pseudo-neuroma,  2,  3,  4,  12,  15 
Pudendal  plexus,  286-287 


R 


prognosis    and 


Radiograph  of  hand,  30 
Radiotherapy,  191,  310 
Reaction  of  degeneration,  39 

complete,  45 

partial,  47 
Reaction,  sweat,  26 

longitudinal,  52 

myotonic,  48 

of  exhaustion,  48 
Reflexes,  20 
Revue  Neurologiqut,  xii 
Roth,  W.,  278 


Sacral  roots,  291—293 
Schwann,  sheath  of,  5,  1 3 
Sciatic  nerve,  anatomy  of,  231 

collateral  and  terminal  branches,  232- 
233 

diagnosis  of  paralysis  of,  262-264 

paralysis  of,  242-257 

treatment  of  paralysis  of,  264-265 
Sciatic  trunk,  paralysis  of,  257-262 
Sclerolytic    medicinal    treatment   of  nerve 

wounds,  31 1-3 1 2 


Sensibility,  of  muscle  to  pressure,  23 

attitude,  33 

cutaneous,  31 

deep,  33 

of  nerve  on  pressure,  34 

osseous,  33 
Sheaths,  synovial,  29 
Sicard,  xii,  23,  82,  191,  302,  306,  307 
Small  sciatic  nerve,  collateral  and  terminal 

branches,  266-267 
Societe  de  Chirurgie  de  Paris,  xii 
Societe  de  Neurologie  de  Paris,  xii 
Steppage,  243,  257 
Stimulation,  unipolar,  37 

bipolar,  37 
Surgical  intervention,  time  of,  300 

choice  of,  301-307 
Suture  of  nerve,  303-304 
Syndrome  of  nerve  interruption,  45,  61-63 

dissociated,  80-8 1 

of  compression,  46,  63-66 
.    of  fibrous  transformation,  47 

of  nerve  irritation,  67-73 

of  regeneration,  73-79 


Tendons,  29 
Tenotomy,  24 
Testut,  243,  250 
Thenar  eminence,  140 

atrophy  of,  182 
Thiosinamin  in  treatment  of  nerve  wounds, 

311-312 
Thomsen's  disease,  48 
Tone,  muscular,  21,  22,  23 
Treatment,  electrical,  308 
Triangle,  Scarpa's,  268,  273,  279 
Trophic  changes,  25,  65,  68,  69,  80 


U 


Ulceration,  28 

Ulnar  nerve,  anatomy,  132 

contractions  resulting  from  slight  neu- 
ritis of,  165 

dissociated  syndromes,  158 

motor  branches  of,  133-134 

motor  syndrome  of  ulnar  paralysis,  136 

neuralgia  of,  158 

neuritis  of,  165 

physiology  of,  136 

sensory  branches  of,  135-136 

sensory  syndrome,  141 

simple  compression  or  recent  interrup- 
tion of,  144 

syndrome  of  prolonged  complete  inter- 
ruption, 149 

syndrome  of  nerve  irritation,  154 

trophic  and  vaso-motor  syndrome,  142 


INDEX 


3*7 


Upper  limb,  ischemic  paralysis  or,  225 
characteristics  of,  226-228 
diagnosis  of,  228-229 


Valleix,  points,  70,  259 

Vaso-motor  changes,  27 

Velpeau,  quadrilateral  square  of,  201 


Velter,  xii 
Vulpian,  >ii 


W 


Waller,  xii 

Weir  Mitchell,  S.,  xii,  66,  71-72,  187 

Weiss,  53 

Wound,  examination  of,  17 

date  of,  1  7 

investigation  of  first  sequelae  of,  18 

nerve  disturbances  of,  18 


THE    END 


I'RINTED    IN    GREAT    BRITAIN    BY    \VI 


LL1AM    CLOWI-S    AND    SONS,    LIMITED,    LONDON    AND    BECCLES. 


14  DAY  USE 

RETURN  TO  DESK  FROM  WHICH  BORROWED   j 

BIOLOGY  LIBRARY 

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